diff --git a/Kharisov/.gitignore b/Kharisov/.gitignore
new file mode 100644
index 00000000..7102a822
--- /dev/null
+++ b/Kharisov/.gitignore
@@ -0,0 +1,6 @@
+_build
+_coverage
+/_esy
+/node_modules
+/esy.lock
+/.melange.eobjs
diff --git a/Kharisov/.ocamlformat b/Kharisov/.ocamlformat
new file mode 100644
index 00000000..97f97080
--- /dev/null
+++ b/Kharisov/.ocamlformat
@@ -0,0 +1,2 @@
+profile=janestreet
+version=0.26.2
diff --git a/Kharisov/.zanuda b/Kharisov/.zanuda
new file mode 100644
index 00000000..0f09b19b
--- /dev/null
+++ b/Kharisov/.zanuda
@@ -0,0 +1 @@
+forward mutability_check ignore REPL.ml
diff --git a/Kharisov/COPYING b/Kharisov/COPYING
new file mode 100644
index 00000000..f288702d
--- /dev/null
+++ b/Kharisov/COPYING
@@ -0,0 +1,674 @@
+ GNU GENERAL PUBLIC LICENSE
+ Version 3, 29 June 2007
+
+ Copyright (C) 2007 Free Software Foundation, Inc.
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+ Preamble
+
+ The GNU General Public License is a free, copyleft license for
+software and other kinds of works.
+
+ The licenses for most software and other practical works are designed
+to take away your freedom to share and change the works. By contrast,
+the GNU General Public License is intended to guarantee your freedom to
+share and change all versions of a program--to make sure it remains free
+software for all its users. We, the Free Software Foundation, use the
+GNU General Public License for most of our software; it applies also to
+any other work released this way by its authors. You can apply it to
+your programs, too.
+
+ When we speak of free software, we are referring to freedom, not
+price. Our General Public Licenses are designed to make sure that you
+have the freedom to distribute copies of free software (and charge for
+them if you wish), that you receive source code or can get it if you
+want it, that you can change the software or use pieces of it in new
+free programs, and that you know you can do these things.
+
+ To protect your rights, we need to prevent others from denying you
+these rights or asking you to surrender the rights. Therefore, you have
+certain responsibilities if you distribute copies of the software, or if
+you modify it: responsibilities to respect the freedom of others.
+
+ For example, if you distribute copies of such a program, whether
+gratis or for a fee, you must pass on to the recipients the same
+freedoms that you received. You must make sure that they, too, receive
+or can get the source code. And you must show them these terms so they
+know their rights.
+
+ Developers that use the GNU GPL protect your rights with two steps:
+(1) assert copyright on the software, and (2) offer you this License
+giving you legal permission to copy, distribute and/or modify it.
+
+ For the developers' and authors' protection, the GPL clearly explains
+that there is no warranty for this free software. For both users' and
+authors' sake, the GPL requires that modified versions be marked as
+changed, so that their problems will not be attributed erroneously to
+authors of previous versions.
+
+ Some devices are designed to deny users access to install or run
+modified versions of the software inside them, although the manufacturer
+can do so. This is fundamentally incompatible with the aim of
+protecting users' freedom to change the software. The systematic
+pattern of such abuse occurs in the area of products for individuals to
+use, which is precisely where it is most unacceptable. Therefore, we
+have designed this version of the GPL to prohibit the practice for those
+products. If such problems arise substantially in other domains, we
+stand ready to extend this provision to those domains in future versions
+of the GPL, as needed to protect the freedom of users.
+
+ Finally, every program is threatened constantly by software patents.
+States should not allow patents to restrict development and use of
+software on general-purpose computers, but in those that do, we wish to
+avoid the special danger that patents applied to a free program could
+make it effectively proprietary. To prevent this, the GPL assures that
+patents cannot be used to render the program non-free.
+
+ The precise terms and conditions for copying, distribution and
+modification follow.
+
+ TERMS AND CONDITIONS
+
+ 0. Definitions.
+
+ "This License" refers to version 3 of the GNU General Public License.
+
+ "Copyright" also means copyright-like laws that apply to other kinds of
+works, such as semiconductor masks.
+
+ "The Program" refers to any copyrightable work licensed under this
+License. Each licensee is addressed as "you". "Licensees" and
+"recipients" may be individuals or organizations.
+
+ To "modify" a work means to copy from or adapt all or part of the work
+in a fashion requiring copyright permission, other than the making of an
+exact copy. The resulting work is called a "modified version" of the
+earlier work or a work "based on" the earlier work.
+
+ A "covered work" means either the unmodified Program or a work based
+on the Program.
+
+ To "propagate" a work means to do anything with it that, without
+permission, would make you directly or secondarily liable for
+infringement under applicable copyright law, except executing it on a
+computer or modifying a private copy. Propagation includes copying,
+distribution (with or without modification), making available to the
+public, and in some countries other activities as well.
+
+ To "convey" a work means any kind of propagation that enables other
+parties to make or receive copies. Mere interaction with a user through
+a computer network, with no transfer of a copy, is not conveying.
+
+ An interactive user interface displays "Appropriate Legal Notices"
+to the extent that it includes a convenient and prominently visible
+feature that (1) displays an appropriate copyright notice, and (2)
+tells the user that there is no warranty for the work (except to the
+extent that warranties are provided), that licensees may convey the
+work under this License, and how to view a copy of this License. If
+the interface presents a list of user commands or options, such as a
+menu, a prominent item in the list meets this criterion.
+
+ 1. Source Code.
+
+ The "source code" for a work means the preferred form of the work
+for making modifications to it. "Object code" means any non-source
+form of a work.
+
+ A "Standard Interface" means an interface that either is an official
+standard defined by a recognized standards body, or, in the case of
+interfaces specified for a particular programming language, one that
+is widely used among developers working in that language.
+
+ The "System Libraries" of an executable work include anything, other
+than the work as a whole, that (a) is included in the normal form of
+packaging a Major Component, but which is not part of that Major
+Component, and (b) serves only to enable use of the work with that
+Major Component, or to implement a Standard Interface for which an
+implementation is available to the public in source code form. A
+"Major Component", in this context, means a major essential component
+(kernel, window system, and so on) of the specific operating system
+(if any) on which the executable work runs, or a compiler used to
+produce the work, or an object code interpreter used to run it.
+
+ The "Corresponding Source" for a work in object code form means all
+the source code needed to generate, install, and (for an executable
+work) run the object code and to modify the work, including scripts to
+control those activities. However, it does not include the work's
+System Libraries, or general-purpose tools or generally available free
+programs which are used unmodified in performing those activities but
+which are not part of the work. For example, Corresponding Source
+includes interface definition files associated with source files for
+the work, and the source code for shared libraries and dynamically
+linked subprograms that the work is specifically designed to require,
+such as by intimate data communication or control flow between those
+subprograms and other parts of the work.
+
+ The Corresponding Source need not include anything that users
+can regenerate automatically from other parts of the Corresponding
+Source.
+
+ The Corresponding Source for a work in source code form is that
+same work.
+
+ 2. Basic Permissions.
+
+ All rights granted under this License are granted for the term of
+copyright on the Program, and are irrevocable provided the stated
+conditions are met. This License explicitly affirms your unlimited
+permission to run the unmodified Program. The output from running a
+covered work is covered by this License only if the output, given its
+content, constitutes a covered work. This License acknowledges your
+rights of fair use or other equivalent, as provided by copyright law.
+
+ You may make, run and propagate covered works that you do not
+convey, without conditions so long as your license otherwise remains
+in force. You may convey covered works to others for the sole purpose
+of having them make modifications exclusively for you, or provide you
+with facilities for running those works, provided that you comply with
+the terms of this License in conveying all material for which you do
+not control copyright. Those thus making or running the covered works
+for you must do so exclusively on your behalf, under your direction
+and control, on terms that prohibit them from making any copies of
+your copyrighted material outside their relationship with you.
+
+ Conveying under any other circumstances is permitted solely under
+the conditions stated below. Sublicensing is not allowed; section 10
+makes it unnecessary.
+
+ 3. Protecting Users' Legal Rights From Anti-Circumvention Law.
+
+ No covered work shall be deemed part of an effective technological
+measure under any applicable law fulfilling obligations under article
+11 of the WIPO copyright treaty adopted on 20 December 1996, or
+similar laws prohibiting or restricting circumvention of such
+measures.
+
+ When you convey a covered work, you waive any legal power to forbid
+circumvention of technological measures to the extent such circumvention
+is effected by exercising rights under this License with respect to
+the covered work, and you disclaim any intention to limit operation or
+modification of the work as a means of enforcing, against the work's
+users, your or third parties' legal rights to forbid circumvention of
+technological measures.
+
+ 4. Conveying Verbatim Copies.
+
+ You may convey verbatim copies of the Program's source code as you
+receive it, in any medium, provided that you conspicuously and
+appropriately publish on each copy an appropriate copyright notice;
+keep intact all notices stating that this License and any
+non-permissive terms added in accord with section 7 apply to the code;
+keep intact all notices of the absence of any warranty; and give all
+recipients a copy of this License along with the Program.
+
+ You may charge any price or no price for each copy that you convey,
+and you may offer support or warranty protection for a fee.
+
+ 5. Conveying Modified Source Versions.
+
+ You may convey a work based on the Program, or the modifications to
+produce it from the Program, in the form of source code under the
+terms of section 4, provided that you also meet all of these conditions:
+
+ a) The work must carry prominent notices stating that you modified
+ it, and giving a relevant date.
+
+ b) The work must carry prominent notices stating that it is
+ released under this License and any conditions added under section
+ 7. This requirement modifies the requirement in section 4 to
+ "keep intact all notices".
+
+ c) You must license the entire work, as a whole, under this
+ License to anyone who comes into possession of a copy. This
+ License will therefore apply, along with any applicable section 7
+ additional terms, to the whole of the work, and all its parts,
+ regardless of how they are packaged. This License gives no
+ permission to license the work in any other way, but it does not
+ invalidate such permission if you have separately received it.
+
+ d) If the work has interactive user interfaces, each must display
+ Appropriate Legal Notices; however, if the Program has interactive
+ interfaces that do not display Appropriate Legal Notices, your
+ work need not make them do so.
+
+ A compilation of a covered work with other separate and independent
+works, which are not by their nature extensions of the covered work,
+and which are not combined with it such as to form a larger program,
+in or on a volume of a storage or distribution medium, is called an
+"aggregate" if the compilation and its resulting copyright are not
+used to limit the access or legal rights of the compilation's users
+beyond what the individual works permit. Inclusion of a covered work
+in an aggregate does not cause this License to apply to the other
+parts of the aggregate.
+
+ 6. Conveying Non-Source Forms.
+
+ You may convey a covered work in object code form under the terms
+of sections 4 and 5, provided that you also convey the
+machine-readable Corresponding Source under the terms of this License,
+in one of these ways:
+
+ a) Convey the object code in, or embodied in, a physical product
+ (including a physical distribution medium), accompanied by the
+ Corresponding Source fixed on a durable physical medium
+ customarily used for software interchange.
+
+ b) Convey the object code in, or embodied in, a physical product
+ (including a physical distribution medium), accompanied by a
+ written offer, valid for at least three years and valid for as
+ long as you offer spare parts or customer support for that product
+ model, to give anyone who possesses the object code either (1) a
+ copy of the Corresponding Source for all the software in the
+ product that is covered by this License, on a durable physical
+ medium customarily used for software interchange, for a price no
+ more than your reasonable cost of physically performing this
+ conveying of source, or (2) access to copy the
+ Corresponding Source from a network server at no charge.
+
+ c) Convey individual copies of the object code with a copy of the
+ written offer to provide the Corresponding Source. This
+ alternative is allowed only occasionally and noncommercially, and
+ only if you received the object code with such an offer, in accord
+ with subsection 6b.
+
+ d) Convey the object code by offering access from a designated
+ place (gratis or for a charge), and offer equivalent access to the
+ Corresponding Source in the same way through the same place at no
+ further charge. You need not require recipients to copy the
+ Corresponding Source along with the object code. If the place to
+ copy the object code is a network server, the Corresponding Source
+ may be on a different server (operated by you or a third party)
+ that supports equivalent copying facilities, provided you maintain
+ clear directions next to the object code saying where to find the
+ Corresponding Source. Regardless of what server hosts the
+ Corresponding Source, you remain obligated to ensure that it is
+ available for as long as needed to satisfy these requirements.
+
+ e) Convey the object code using peer-to-peer transmission, provided
+ you inform other peers where the object code and Corresponding
+ Source of the work are being offered to the general public at no
+ charge under subsection 6d.
+
+ A separable portion of the object code, whose source code is excluded
+from the Corresponding Source as a System Library, need not be
+included in conveying the object code work.
+
+ A "User Product" is either (1) a "consumer product", which means any
+tangible personal property which is normally used for personal, family,
+or household purposes, or (2) anything designed or sold for incorporation
+into a dwelling. In determining whether a product is a consumer product,
+doubtful cases shall be resolved in favor of coverage. For a particular
+product received by a particular user, "normally used" refers to a
+typical or common use of that class of product, regardless of the status
+of the particular user or of the way in which the particular user
+actually uses, or expects or is expected to use, the product. A product
+is a consumer product regardless of whether the product has substantial
+commercial, industrial or non-consumer uses, unless such uses represent
+the only significant mode of use of the product.
+
+ "Installation Information" for a User Product means any methods,
+procedures, authorization keys, or other information required to install
+and execute modified versions of a covered work in that User Product from
+a modified version of its Corresponding Source. The information must
+suffice to ensure that the continued functioning of the modified object
+code is in no case prevented or interfered with solely because
+modification has been made.
+
+ If you convey an object code work under this section in, or with, or
+specifically for use in, a User Product, and the conveying occurs as
+part of a transaction in which the right of possession and use of the
+User Product is transferred to the recipient in perpetuity or for a
+fixed term (regardless of how the transaction is characterized), the
+Corresponding Source conveyed under this section must be accompanied
+by the Installation Information. But this requirement does not apply
+if neither you nor any third party retains the ability to install
+modified object code on the User Product (for example, the work has
+been installed in ROM).
+
+ The requirement to provide Installation Information does not include a
+requirement to continue to provide support service, warranty, or updates
+for a work that has been modified or installed by the recipient, or for
+the User Product in which it has been modified or installed. Access to a
+network may be denied when the modification itself materially and
+adversely affects the operation of the network or violates the rules and
+protocols for communication across the network.
+
+ Corresponding Source conveyed, and Installation Information provided,
+in accord with this section must be in a format that is publicly
+documented (and with an implementation available to the public in
+source code form), and must require no special password or key for
+unpacking, reading or copying.
+
+ 7. Additional Terms.
+
+ "Additional permissions" are terms that supplement the terms of this
+License by making exceptions from one or more of its conditions.
+Additional permissions that are applicable to the entire Program shall
+be treated as though they were included in this License, to the extent
+that they are valid under applicable law. If additional permissions
+apply only to part of the Program, that part may be used separately
+under those permissions, but the entire Program remains governed by
+this License without regard to the additional permissions.
+
+ When you convey a copy of a covered work, you may at your option
+remove any additional permissions from that copy, or from any part of
+it. (Additional permissions may be written to require their own
+removal in certain cases when you modify the work.) You may place
+additional permissions on material, added by you to a covered work,
+for which you have or can give appropriate copyright permission.
+
+ Notwithstanding any other provision of this License, for material you
+add to a covered work, you may (if authorized by the copyright holders of
+that material) supplement the terms of this License with terms:
+
+ a) Disclaiming warranty or limiting liability differently from the
+ terms of sections 15 and 16 of this License; or
+
+ b) Requiring preservation of specified reasonable legal notices or
+ author attributions in that material or in the Appropriate Legal
+ Notices displayed by works containing it; or
+
+ c) Prohibiting misrepresentation of the origin of that material, or
+ requiring that modified versions of such material be marked in
+ reasonable ways as different from the original version; or
+
+ d) Limiting the use for publicity purposes of names of licensors or
+ authors of the material; or
+
+ e) Declining to grant rights under trademark law for use of some
+ trade names, trademarks, or service marks; or
+
+ f) Requiring indemnification of licensors and authors of that
+ material by anyone who conveys the material (or modified versions of
+ it) with contractual assumptions of liability to the recipient, for
+ any liability that these contractual assumptions directly impose on
+ those licensors and authors.
+
+ All other non-permissive additional terms are considered "further
+restrictions" within the meaning of section 10. If the Program as you
+received it, or any part of it, contains a notice stating that it is
+governed by this License along with a term that is a further
+restriction, you may remove that term. If a license document contains
+a further restriction but permits relicensing or conveying under this
+License, you may add to a covered work material governed by the terms
+of that license document, provided that the further restriction does
+not survive such relicensing or conveying.
+
+ If you add terms to a covered work in accord with this section, you
+must place, in the relevant source files, a statement of the
+additional terms that apply to those files, or a notice indicating
+where to find the applicable terms.
+
+ Additional terms, permissive or non-permissive, may be stated in the
+form of a separately written license, or stated as exceptions;
+the above requirements apply either way.
+
+ 8. Termination.
+
+ You may not propagate or modify a covered work except as expressly
+provided under this License. Any attempt otherwise to propagate or
+modify it is void, and will automatically terminate your rights under
+this License (including any patent licenses granted under the third
+paragraph of section 11).
+
+ However, if you cease all violation of this License, then your
+license from a particular copyright holder is reinstated (a)
+provisionally, unless and until the copyright holder explicitly and
+finally terminates your license, and (b) permanently, if the copyright
+holder fails to notify you of the violation by some reasonable means
+prior to 60 days after the cessation.
+
+ Moreover, your license from a particular copyright holder is
+reinstated permanently if the copyright holder notifies you of the
+violation by some reasonable means, this is the first time you have
+received notice of violation of this License (for any work) from that
+copyright holder, and you cure the violation prior to 30 days after
+your receipt of the notice.
+
+ Termination of your rights under this section does not terminate the
+licenses of parties who have received copies or rights from you under
+this License. If your rights have been terminated and not permanently
+reinstated, you do not qualify to receive new licenses for the same
+material under section 10.
+
+ 9. Acceptance Not Required for Having Copies.
+
+ You are not required to accept this License in order to receive or
+run a copy of the Program. Ancillary propagation of a covered work
+occurring solely as a consequence of using peer-to-peer transmission
+to receive a copy likewise does not require acceptance. However,
+nothing other than this License grants you permission to propagate or
+modify any covered work. These actions infringe copyright if you do
+not accept this License. Therefore, by modifying or propagating a
+covered work, you indicate your acceptance of this License to do so.
+
+ 10. Automatic Licensing of Downstream Recipients.
+
+ Each time you convey a covered work, the recipient automatically
+receives a license from the original licensors, to run, modify and
+propagate that work, subject to this License. You are not responsible
+for enforcing compliance by third parties with this License.
+
+ An "entity transaction" is a transaction transferring control of an
+organization, or substantially all assets of one, or subdividing an
+organization, or merging organizations. If propagation of a covered
+work results from an entity transaction, each party to that
+transaction who receives a copy of the work also receives whatever
+licenses to the work the party's predecessor in interest had or could
+give under the previous paragraph, plus a right to possession of the
+Corresponding Source of the work from the predecessor in interest, if
+the predecessor has it or can get it with reasonable efforts.
+
+ You may not impose any further restrictions on the exercise of the
+rights granted or affirmed under this License. For example, you may
+not impose a license fee, royalty, or other charge for exercise of
+rights granted under this License, and you may not initiate litigation
+(including a cross-claim or counterclaim in a lawsuit) alleging that
+any patent claim is infringed by making, using, selling, offering for
+sale, or importing the Program or any portion of it.
+
+ 11. Patents.
+
+ A "contributor" is a copyright holder who authorizes use under this
+License of the Program or a work on which the Program is based. The
+work thus licensed is called the contributor's "contributor version".
+
+ A contributor's "essential patent claims" are all patent claims
+owned or controlled by the contributor, whether already acquired or
+hereafter acquired, that would be infringed by some manner, permitted
+by this License, of making, using, or selling its contributor version,
+but do not include claims that would be infringed only as a
+consequence of further modification of the contributor version. For
+purposes of this definition, "control" includes the right to grant
+patent sublicenses in a manner consistent with the requirements of
+this License.
+
+ Each contributor grants you a non-exclusive, worldwide, royalty-free
+patent license under the contributor's essential patent claims, to
+make, use, sell, offer for sale, import and otherwise run, modify and
+propagate the contents of its contributor version.
+
+ In the following three paragraphs, a "patent license" is any express
+agreement or commitment, however denominated, not to enforce a patent
+(such as an express permission to practice a patent or covenant not to
+sue for patent infringement). To "grant" such a patent license to a
+party means to make such an agreement or commitment not to enforce a
+patent against the party.
+
+ If you convey a covered work, knowingly relying on a patent license,
+and the Corresponding Source of the work is not available for anyone
+to copy, free of charge and under the terms of this License, through a
+publicly available network server or other readily accessible means,
+then you must either (1) cause the Corresponding Source to be so
+available, or (2) arrange to deprive yourself of the benefit of the
+patent license for this particular work, or (3) arrange, in a manner
+consistent with the requirements of this License, to extend the patent
+license to downstream recipients. "Knowingly relying" means you have
+actual knowledge that, but for the patent license, your conveying the
+covered work in a country, or your recipient's use of the covered work
+in a country, would infringe one or more identifiable patents in that
+country that you have reason to believe are valid.
+
+ If, pursuant to or in connection with a single transaction or
+arrangement, you convey, or propagate by procuring conveyance of, a
+covered work, and grant a patent license to some of the parties
+receiving the covered work authorizing them to use, propagate, modify
+or convey a specific copy of the covered work, then the patent license
+you grant is automatically extended to all recipients of the covered
+work and works based on it.
+
+ A patent license is "discriminatory" if it does not include within
+the scope of its coverage, prohibits the exercise of, or is
+conditioned on the non-exercise of one or more of the rights that are
+specifically granted under this License. You may not convey a covered
+work if you are a party to an arrangement with a third party that is
+in the business of distributing software, under which you make payment
+to the third party based on the extent of your activity of conveying
+the work, and under which the third party grants, to any of the
+parties who would receive the covered work from you, a discriminatory
+patent license (a) in connection with copies of the covered work
+conveyed by you (or copies made from those copies), or (b) primarily
+for and in connection with specific products or compilations that
+contain the covered work, unless you entered into that arrangement,
+or that patent license was granted, prior to 28 March 2007.
+
+ Nothing in this License shall be construed as excluding or limiting
+any implied license or other defenses to infringement that may
+otherwise be available to you under applicable patent law.
+
+ 12. No Surrender of Others' Freedom.
+
+ If conditions are imposed on you (whether by court order, agreement or
+otherwise) that contradict the conditions of this License, they do not
+excuse you from the conditions of this License. If you cannot convey a
+covered work so as to satisfy simultaneously your obligations under this
+License and any other pertinent obligations, then as a consequence you may
+not convey it at all. For example, if you agree to terms that obligate you
+to collect a royalty for further conveying from those to whom you convey
+the Program, the only way you could satisfy both those terms and this
+License would be to refrain entirely from conveying the Program.
+
+ 13. Use with the GNU Affero General Public License.
+
+ Notwithstanding any other provision of this License, you have
+permission to link or combine any covered work with a work licensed
+under version 3 of the GNU Affero General Public License into a single
+combined work, and to convey the resulting work. The terms of this
+License will continue to apply to the part which is the covered work,
+but the special requirements of the GNU Affero General Public License,
+section 13, concerning interaction through a network will apply to the
+combination as such.
+
+ 14. Revised Versions of this License.
+
+ The Free Software Foundation may publish revised and/or new versions of
+the GNU General Public License from time to time. Such new versions will
+be similar in spirit to the present version, but may differ in detail to
+address new problems or concerns.
+
+ Each version is given a distinguishing version number. If the
+Program specifies that a certain numbered version of the GNU General
+Public License "or any later version" applies to it, you have the
+option of following the terms and conditions either of that numbered
+version or of any later version published by the Free Software
+Foundation. If the Program does not specify a version number of the
+GNU General Public License, you may choose any version ever published
+by the Free Software Foundation.
+
+ If the Program specifies that a proxy can decide which future
+versions of the GNU General Public License can be used, that proxy's
+public statement of acceptance of a version permanently authorizes you
+to choose that version for the Program.
+
+ Later license versions may give you additional or different
+permissions. However, no additional obligations are imposed on any
+author or copyright holder as a result of your choosing to follow a
+later version.
+
+ 15. Disclaimer of Warranty.
+
+ THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
+APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
+HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY
+OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
+THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM
+IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
+ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
+
+ 16. Limitation of Liability.
+
+ IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
+THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
+GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
+USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
+DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
+PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
+EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
+SUCH DAMAGES.
+
+ 17. Interpretation of Sections 15 and 16.
+
+ If the disclaimer of warranty and limitation of liability provided
+above cannot be given local legal effect according to their terms,
+reviewing courts shall apply local law that most closely approximates
+an absolute waiver of all civil liability in connection with the
+Program, unless a warranty or assumption of liability accompanies a
+copy of the Program in return for a fee.
+
+ END OF TERMS AND CONDITIONS
+
+ How to Apply These Terms to Your New Programs
+
+ If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+ To do so, attach the following notices to the program. It is safest
+to attach them to the start of each source file to most effectively
+state the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+
+ Copyright (C)
+
+ This program is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see .
+
+Also add information on how to contact you by electronic and paper mail.
+
+ If the program does terminal interaction, make it output a short
+notice like this when it starts in an interactive mode:
+
+ Copyright (C)
+ This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+ This is free software, and you are welcome to redistribute it
+ under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License. Of course, your program's commands
+might be different; for a GUI interface, you would use an "about box".
+
+ You should also get your employer (if you work as a programmer) or school,
+if any, to sign a "copyright disclaimer" for the program, if necessary.
+For more information on this, and how to apply and follow the GNU GPL, see
+.
+
+ The GNU General Public License does not permit incorporating your program
+into proprietary programs. If your program is a subroutine library, you
+may consider it more useful to permit linking proprietary applications with
+the library. If this is what you want to do, use the GNU Lesser General
+Public License instead of this License. But first, please read
+.
diff --git a/Kharisov/COPYING.CC0 b/Kharisov/COPYING.CC0
new file mode 100644
index 00000000..0e259d42
--- /dev/null
+++ b/Kharisov/COPYING.CC0
@@ -0,0 +1,121 @@
+Creative Commons Legal Code
+
+CC0 1.0 Universal
+
+ CREATIVE COMMONS CORPORATION IS NOT A LAW FIRM AND DOES NOT PROVIDE
+ LEGAL SERVICES. DISTRIBUTION OF THIS DOCUMENT DOES NOT CREATE AN
+ ATTORNEY-CLIENT RELATIONSHIP. CREATIVE COMMONS PROVIDES THIS
+ INFORMATION ON AN "AS-IS" BASIS. CREATIVE COMMONS MAKES NO WARRANTIES
+ REGARDING THE USE OF THIS DOCUMENT OR THE INFORMATION OR WORKS
+ PROVIDED HEREUNDER, AND DISCLAIMS LIABILITY FOR DAMAGES RESULTING FROM
+ THE USE OF THIS DOCUMENT OR THE INFORMATION OR WORKS PROVIDED
+ HEREUNDER.
+
+Statement of Purpose
+
+The laws of most jurisdictions throughout the world automatically confer
+exclusive Copyright and Related Rights (defined below) upon the creator
+and subsequent owner(s) (each and all, an "owner") of an original work of
+authorship and/or a database (each, a "Work").
+
+Certain owners wish to permanently relinquish those rights to a Work for
+the purpose of contributing to a commons of creative, cultural and
+scientific works ("Commons") that the public can reliably and without fear
+of later claims of infringement build upon, modify, incorporate in other
+works, reuse and redistribute as freely as possible in any form whatsoever
+and for any purposes, including without limitation commercial purposes.
+These owners may contribute to the Commons to promote the ideal of a free
+culture and the further production of creative, cultural and scientific
+works, or to gain reputation or greater distribution for their Work in
+part through the use and efforts of others.
+
+For these and/or other purposes and motivations, and without any
+expectation of additional consideration or compensation, the person
+associating CC0 with a Work (the "Affirmer"), to the extent that he or she
+is an owner of Copyright and Related Rights in the Work, voluntarily
+elects to apply CC0 to the Work and publicly distribute the Work under its
+terms, with knowledge of his or her Copyright and Related Rights in the
+Work and the meaning and intended legal effect of CC0 on those rights.
+
+1. Copyright and Related Rights. A Work made available under CC0 may be
+protected by copyright and related or neighboring rights ("Copyright and
+Related Rights"). Copyright and Related Rights include, but are not
+limited to, the following:
+
+ i. the right to reproduce, adapt, distribute, perform, display,
+ communicate, and translate a Work;
+ ii. moral rights retained by the original author(s) and/or performer(s);
+iii. publicity and privacy rights pertaining to a person's image or
+ likeness depicted in a Work;
+ iv. rights protecting against unfair competition in regards to a Work,
+ subject to the limitations in paragraph 4(a), below;
+ v. rights protecting the extraction, dissemination, use and reuse of data
+ in a Work;
+ vi. database rights (such as those arising under Directive 96/9/EC of the
+ European Parliament and of the Council of 11 March 1996 on the legal
+ protection of databases, and under any national implementation
+ thereof, including any amended or successor version of such
+ directive); and
+vii. other similar, equivalent or corresponding rights throughout the
+ world based on applicable law or treaty, and any national
+ implementations thereof.
+
+2. Waiver. To the greatest extent permitted by, but not in contravention
+of, applicable law, Affirmer hereby overtly, fully, permanently,
+irrevocably and unconditionally waives, abandons, and surrenders all of
+Affirmer's Copyright and Related Rights and associated claims and causes
+of action, whether now known or unknown (including existing as well as
+future claims and causes of action), in the Work (i) in all territories
+worldwide, (ii) for the maximum duration provided by applicable law or
+treaty (including future time extensions), (iii) in any current or future
+medium and for any number of copies, and (iv) for any purpose whatsoever,
+including without limitation commercial, advertising or promotional
+purposes (the "Waiver"). Affirmer makes the Waiver for the benefit of each
+member of the public at large and to the detriment of Affirmer's heirs and
+successors, fully intending that such Waiver shall not be subject to
+revocation, rescission, cancellation, termination, or any other legal or
+equitable action to disrupt the quiet enjoyment of the Work by the public
+as contemplated by Affirmer's express Statement of Purpose.
+
+3. Public License Fallback. Should any part of the Waiver for any reason
+be judged legally invalid or ineffective under applicable law, then the
+Waiver shall be preserved to the maximum extent permitted taking into
+account Affirmer's express Statement of Purpose. In addition, to the
+extent the Waiver is so judged Affirmer hereby grants to each affected
+person a royalty-free, non transferable, non sublicensable, non exclusive,
+irrevocable and unconditional license to exercise Affirmer's Copyright and
+Related Rights in the Work (i) in all territories worldwide, (ii) for the
+maximum duration provided by applicable law or treaty (including future
+time extensions), (iii) in any current or future medium and for any number
+of copies, and (iv) for any purpose whatsoever, including without
+limitation commercial, advertising or promotional purposes (the
+"License"). The License shall be deemed effective as of the date CC0 was
+applied by Affirmer to the Work. Should any part of the License for any
+reason be judged legally invalid or ineffective under applicable law, such
+partial invalidity or ineffectiveness shall not invalidate the remainder
+of the License, and in such case Affirmer hereby affirms that he or she
+will not (i) exercise any of his or her remaining Copyright and Related
+Rights in the Work or (ii) assert any associated claims and causes of
+action with respect to the Work, in either case contrary to Affirmer's
+express Statement of Purpose.
+
+4. Limitations and Disclaimers.
+
+ a. No trademark or patent rights held by Affirmer are waived, abandoned,
+ surrendered, licensed or otherwise affected by this document.
+ b. Affirmer offers the Work as-is and makes no representations or
+ warranties of any kind concerning the Work, express, implied,
+ statutory or otherwise, including without limitation warranties of
+ title, merchantability, fitness for a particular purpose, non
+ infringement, or the absence of latent or other defects, accuracy, or
+ the present or absence of errors, whether or not discoverable, all to
+ the greatest extent permissible under applicable law.
+ c. Affirmer disclaims responsibility for clearing rights of other persons
+ that may apply to the Work or any use thereof, including without
+ limitation any person's Copyright and Related Rights in the Work.
+ Further, Affirmer disclaims responsibility for obtaining any necessary
+ consents, permissions or other rights required for any use of the
+ Work.
+ d. Affirmer understands and acknowledges that Creative Commons is not a
+ party to this document and has no duty or obligation with respect to
+ this CC0 or use of the Work.
diff --git a/Kharisov/COPYING.LESSER b/Kharisov/COPYING.LESSER
new file mode 100644
index 00000000..0a041280
--- /dev/null
+++ b/Kharisov/COPYING.LESSER
@@ -0,0 +1,165 @@
+ GNU LESSER GENERAL PUBLIC LICENSE
+ Version 3, 29 June 2007
+
+ Copyright (C) 2007 Free Software Foundation, Inc.
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+
+ This version of the GNU Lesser General Public License incorporates
+the terms and conditions of version 3 of the GNU General Public
+License, supplemented by the additional permissions listed below.
+
+ 0. Additional Definitions.
+
+ As used herein, "this License" refers to version 3 of the GNU Lesser
+General Public License, and the "GNU GPL" refers to version 3 of the GNU
+General Public License.
+
+ "The Library" refers to a covered work governed by this License,
+other than an Application or a Combined Work as defined below.
+
+ An "Application" is any work that makes use of an interface provided
+by the Library, but which is not otherwise based on the Library.
+Defining a subclass of a class defined by the Library is deemed a mode
+of using an interface provided by the Library.
+
+ A "Combined Work" is a work produced by combining or linking an
+Application with the Library. The particular version of the Library
+with which the Combined Work was made is also called the "Linked
+Version".
+
+ The "Minimal Corresponding Source" for a Combined Work means the
+Corresponding Source for the Combined Work, excluding any source code
+for portions of the Combined Work that, considered in isolation, are
+based on the Application, and not on the Linked Version.
+
+ The "Corresponding Application Code" for a Combined Work means the
+object code and/or source code for the Application, including any data
+and utility programs needed for reproducing the Combined Work from the
+Application, but excluding the System Libraries of the Combined Work.
+
+ 1. Exception to Section 3 of the GNU GPL.
+
+ You may convey a covered work under sections 3 and 4 of this License
+without being bound by section 3 of the GNU GPL.
+
+ 2. Conveying Modified Versions.
+
+ If you modify a copy of the Library, and, in your modifications, a
+facility refers to a function or data to be supplied by an Application
+that uses the facility (other than as an argument passed when the
+facility is invoked), then you may convey a copy of the modified
+version:
+
+ a) under this License, provided that you make a good faith effort to
+ ensure that, in the event an Application does not supply the
+ function or data, the facility still operates, and performs
+ whatever part of its purpose remains meaningful, or
+
+ b) under the GNU GPL, with none of the additional permissions of
+ this License applicable to that copy.
+
+ 3. Object Code Incorporating Material from Library Header Files.
+
+ The object code form of an Application may incorporate material from
+a header file that is part of the Library. You may convey such object
+code under terms of your choice, provided that, if the incorporated
+material is not limited to numerical parameters, data structure
+layouts and accessors, or small macros, inline functions and templates
+(ten or fewer lines in length), you do both of the following:
+
+ a) Give prominent notice with each copy of the object code that the
+ Library is used in it and that the Library and its use are
+ covered by this License.
+
+ b) Accompany the object code with a copy of the GNU GPL and this license
+ document.
+
+ 4. Combined Works.
+
+ You may convey a Combined Work under terms of your choice that,
+taken together, effectively do not restrict modification of the
+portions of the Library contained in the Combined Work and reverse
+engineering for debugging such modifications, if you also do each of
+the following:
+
+ a) Give prominent notice with each copy of the Combined Work that
+ the Library is used in it and that the Library and its use are
+ covered by this License.
+
+ b) Accompany the Combined Work with a copy of the GNU GPL and this license
+ document.
+
+ c) For a Combined Work that displays copyright notices during
+ execution, include the copyright notice for the Library among
+ these notices, as well as a reference directing the user to the
+ copies of the GNU GPL and this license document.
+
+ d) Do one of the following:
+
+ 0) Convey the Minimal Corresponding Source under the terms of this
+ License, and the Corresponding Application Code in a form
+ suitable for, and under terms that permit, the user to
+ recombine or relink the Application with a modified version of
+ the Linked Version to produce a modified Combined Work, in the
+ manner specified by section 6 of the GNU GPL for conveying
+ Corresponding Source.
+
+ 1) Use a suitable shared library mechanism for linking with the
+ Library. A suitable mechanism is one that (a) uses at run time
+ a copy of the Library already present on the user's computer
+ system, and (b) will operate properly with a modified version
+ of the Library that is interface-compatible with the Linked
+ Version.
+
+ e) Provide Installation Information, but only if you would otherwise
+ be required to provide such information under section 6 of the
+ GNU GPL, and only to the extent that such information is
+ necessary to install and execute a modified version of the
+ Combined Work produced by recombining or relinking the
+ Application with a modified version of the Linked Version. (If
+ you use option 4d0, the Installation Information must accompany
+ the Minimal Corresponding Source and Corresponding Application
+ Code. If you use option 4d1, you must provide the Installation
+ Information in the manner specified by section 6 of the GNU GPL
+ for conveying Corresponding Source.)
+
+ 5. Combined Libraries.
+
+ You may place library facilities that are a work based on the
+Library side by side in a single library together with other library
+facilities that are not Applications and are not covered by this
+License, and convey such a combined library under terms of your
+choice, if you do both of the following:
+
+ a) Accompany the combined library with a copy of the same work based
+ on the Library, uncombined with any other library facilities,
+ conveyed under the terms of this License.
+
+ b) Give prominent notice with the combined library that part of it
+ is a work based on the Library, and explaining where to find the
+ accompanying uncombined form of the same work.
+
+ 6. Revised Versions of the GNU Lesser General Public License.
+
+ The Free Software Foundation may publish revised and/or new versions
+of the GNU Lesser General Public License from time to time. Such new
+versions will be similar in spirit to the present version, but may
+differ in detail to address new problems or concerns.
+
+ Each version is given a distinguishing version number. If the
+Library as you received it specifies that a certain numbered version
+of the GNU Lesser General Public License "or any later version"
+applies to it, you have the option of following the terms and
+conditions either of that published version or of any later version
+published by the Free Software Foundation. If the Library as you
+received it does not specify a version number of the GNU Lesser
+General Public License, you may choose any version of the GNU Lesser
+General Public License ever published by the Free Software Foundation.
+
+ If the Library as you received it specifies that a proxy can decide
+whether future versions of the GNU Lesser General Public License shall
+apply, that proxy's public statement of acceptance of any version is
+permanent authorization for you to choose that version for the
+Library.
diff --git a/Kharisov/Kharisov.opam b/Kharisov/Kharisov.opam
new file mode 100644
index 00000000..4df5aeb1
--- /dev/null
+++ b/Kharisov/Kharisov.opam
@@ -0,0 +1,42 @@
+# This file is generated by dune, edit dune-project instead
+opam-version: "2.0"
+version: "0.1"
+synopsis: "MiniML interpreter"
+description:
+ "Interpreter of MiniML (Ocaml-like functional programming language) subset"
+maintainer: ["Bogdan Kharisov bbh4rris@gmail.com"]
+authors: ["Bogdan Kharisov bbh4rris@gmail.com"]
+license: "LGPL-3.0-or-later WITH OCaml-LGPL-linking-exception"
+homepage: "https://github.com/Kakadu/fp25"
+doc: "https://kakadu.github.io/fp25/docs/Lambda"
+bug-reports: "https://github.com/Kakadu/fp25"
+depends: [
+ "dune" {>= "3.7" & = "3.21.0"}
+ "angstrom" {= "0.16.0"}
+ "base"
+ "ppx_inline_test" {with-test}
+ "ppx_expect"
+ "ppx_deriving"
+ "bisect_ppx"
+ "qcheck" {>= "0.18"}
+ "odoc" {with-doc}
+ "ocamlformat" {build & = "0.26.2"}
+]
+build: [
+ ["dune" "subst"] {dev}
+ [
+ "dune"
+ "build"
+ "-p"
+ name
+ "-j"
+ jobs
+ "@install"
+ "@runtest" {with-test}
+ "@doc" {with-doc}
+ ]
+]
+pin-depends: [
+ ["ppx_deriving_qcheck.0.6" "git+https://github.com/c-cube/qcheck.git#42429bf06ba12373cad02b1404f50d0ad6238af5"]
+]
+# Don't edit '*.opam' file manually. Use 'dune b @install'
diff --git a/Kharisov/Kharisov.opam.template b/Kharisov/Kharisov.opam.template
new file mode 100644
index 00000000..480da691
--- /dev/null
+++ b/Kharisov/Kharisov.opam.template
@@ -0,0 +1,4 @@
+pin-depends: [
+ ["ppx_deriving_qcheck.0.6" "git+https://github.com/c-cube/qcheck.git#42429bf06ba12373cad02b1404f50d0ad6238af5"]
+]
+# Don't edit '*.opam' file manually. Use 'dune b @install'
diff --git a/Kharisov/Makefile b/Kharisov/Makefile
new file mode 100644
index 00000000..e234db4b
--- /dev/null
+++ b/Kharisov/Makefile
@@ -0,0 +1,49 @@
+.PHONY: repl tests test fmt lint celan
+
+all:
+ dune build
+
+repl:
+ dune build ./REPL.exe && rlwrap _build/default/REPL.exe
+
+tests: test
+test:
+ dune runtest
+
+celan: clean
+clean:
+ @$(RM) -r _build _coverage
+
+fmt:
+ dune build @fmt --auto-promote
+
+lint:
+ dune build @lint --force
+
+release:
+ dune build --profile=release
+ dune runtest --profile=release
+
+install:
+ dune b @install --profile=release
+ dune install
+
+ODIG_SWITCHES = --odoc-theme=odig.gruvbox.light
+ODIG_SWITCHES += --no-tag-index
+ODIG_SWITCHES += --no-pkg-deps
+odig:
+ odig odoc $(ODIG_SWITCHES) Lambda
+
+TEST_COV_D = /tmp/cov
+COVERAGE_OPTS = --coverage-path $(TEST_COV_D) --expect lib/ --expect tests/
+
+.PHONY: test_coverage coverage
+test_coverage: coverage
+coverage:
+ $(RM) -r $(TEST_COV_D)
+ mkdir -p $(TEST_COV_D)
+ BISECT_FILE=$(TEST_COV_D)/language dune runtest --no-print-directory \
+ --instrument-with bisect_ppx --force
+ bisect-ppx-report html $(COVERAGE_OPTS)
+ bisect-ppx-report summary $(COVERAGE_OPTS)
+ @echo "Use 'xdg-open _coverage/index.html' to see coverage report"
diff --git a/Kharisov/bin/REPL.ml b/Kharisov/bin/REPL.ml
new file mode 100644
index 00000000..63aa6eb8
--- /dev/null
+++ b/Kharisov/bin/REPL.ml
@@ -0,0 +1,34 @@
+[@@@ocaml.text "/*"]
+
+(** Copyright 2021-2024, Kakadu and contributors *)
+
+(** SPDX-License-Identifier: LGPL-3.0-or-later *)
+
+[@@@ocaml.text "/*"]
+
+let usage () =
+ Printf.eprintf
+ "usage: %s [steps]\nsteps: positive integer, default 10000\n"
+ Sys.argv.(0);
+ exit 1
+;;
+
+let () =
+ let steps =
+ match Array.length Sys.argv with
+ | 1 -> 10_000
+ | 2 ->
+ (match int_of_string_opt Sys.argv.(1) with
+ | Some n when n > 0 -> n
+ | _ -> usage ())
+ | _ -> usage ()
+ in
+ let src = In_channel.input_all In_channel.stdin in
+ match Interpret_lib.Interpret.run ~steps src with
+ | Ok (v, output) ->
+ List.iter print_endline output;
+ print_endline (Interpret_lib.Interpret.format_value v)
+ | Error e ->
+ print_endline (Interpret_lib.Interpret.format_error e);
+ exit 1
+;;
diff --git a/Kharisov/bin/REPL.mli b/Kharisov/bin/REPL.mli
new file mode 100644
index 00000000..c1135e06
--- /dev/null
+++ b/Kharisov/bin/REPL.mli
@@ -0,0 +1,7 @@
+[@@@ocaml.text "/*"]
+
+(** Copyright 2021-2024, Kakadu and contributors *)
+
+(** SPDX-License-Identifier: LGPL-3.0-or-later *)
+
+[@@@ocaml.text "/*"]
diff --git a/Kharisov/bin/dune b/Kharisov/bin/dune
new file mode 100644
index 00000000..a2c10531
--- /dev/null
+++ b/Kharisov/bin/dune
@@ -0,0 +1,7 @@
+(executable
+ (name REPL)
+ (public_name Kharisov.REPL)
+ (modules REPL)
+ (libraries interpret_lib)
+ (instrumentation
+ (backend bisect_ppx)))
diff --git a/Kharisov/dune b/Kharisov/dune
new file mode 100644
index 00000000..98e54536
--- /dev/null
+++ b/Kharisov/dune
@@ -0,0 +1,7 @@
+(env
+ (dev
+ (flags
+ (:standard -alert @deprecated -warn-error -A -w -3-9-32-34-58)))
+ (release
+ (flags
+ (:standard -alert @deprecated -warn-error +A -w +A-4-40-42-44-70))))
diff --git a/Kharisov/dune-project b/Kharisov/dune-project
new file mode 100644
index 00000000..1403f0fb
--- /dev/null
+++ b/Kharisov/dune-project
@@ -0,0 +1,43 @@
+(lang dune 3.7)
+
+(generate_opam_files true)
+
+(cram enable)
+
+(license "LGPL-3.0-or-later WITH OCaml-LGPL-linking-exception")
+
+(authors "Bogdan Kharisov bbh4rris@gmail.com")
+
+(maintainers "Bogdan Kharisov bbh4rris@gmail.com")
+
+(bug_reports "https://github.com/Kakadu/fp25")
+
+(homepage "https://github.com/Kakadu/fp25")
+
+(package
+ (name Kharisov) ; FIXME and regenerate .opam file using 'dune build @install'
+ (synopsis "MiniML interpreter")
+ (description
+ "Interpreter of MiniML (Ocaml-like functional programming language) subset")
+ (documentation "https://kakadu.github.io/fp25/docs/Lambda")
+ (version 0.1)
+ (depends
+ (dune
+ (= "3.21.0"))
+ (angstrom
+ (= "0.16.0"))
+ base
+ (ppx_inline_test :with-test)
+ ppx_expect
+ ppx_deriving
+ bisect_ppx
+ (qcheck
+ (>= "0.18"))
+ (odoc :with-doc)
+ (ocamlformat
+ (and
+ :build
+ (= "0.26.2")))
+ ; base
+ ; After adding dependencies to 'dune' files add the same dependecies here too
+ ))
diff --git a/Kharisov/lib/ast.mli b/Kharisov/lib/ast.mli
new file mode 100644
index 00000000..50295571
--- /dev/null
+++ b/Kharisov/lib/ast.mli
@@ -0,0 +1,38 @@
+[@@@ocaml.text "/*"]
+
+(** Copyright 2021-2024, Kakadu and contributors *)
+
+(** SPDX-License-Identifier: LGPL-3.0-or-later *)
+
+[@@@ocaml.text "/*"]
+
+(* identifier *)
+type id = string
+
+(* binary operator *)
+type binop =
+ | Add (** [+] *)
+ | Sub (** [-] *)
+ | Mul (** [*] *)
+ | Div (** [/] *)
+ | Eq (** [=] *)
+ | Neq (** [<>] *)
+ | Lt (** [<] *)
+ | Le (** [<=] *)
+ | Gt (** [>] *)
+ | Ge (** [>=] *)
+
+(* recursion flag for let bindings *)
+type rec_flag =
+ | Rec (** [let rec] *)
+ | NonRec (** [let] *)
+
+(* expression *)
+type expr =
+ | EConst of int (** integer literal: [42], [-1] *)
+ | EVar of id (** variable: [x], [fact] *)
+ | EBinop of binop * expr * expr (** binary operation: [e1 + e2] *)
+ | EIf of expr * expr * expr (** conditional: [if c then e1 else e2] *)
+ | EFun of id * expr (** abstraction: [fun x -> e] *)
+ | EApp of expr * expr (** application: [f x] *)
+ | ELet of rec_flag * id * expr * expr (** binding: [let (rec)? x = e1 in e2] *)
diff --git a/Kharisov/lib/dune b/Kharisov/lib/dune
new file mode 100644
index 00000000..79e3aae5
--- /dev/null
+++ b/Kharisov/lib/dune
@@ -0,0 +1,8 @@
+(library
+ (name interpret_lib)
+ (public_name Kharisov.Lib)
+ (modules Ast Interpret Parser Pprint)
+ (modules_without_implementation Ast)
+ (libraries angstrom)
+ (instrumentation
+ (backend bisect_ppx)))
diff --git a/Kharisov/lib/interpret.ml b/Kharisov/lib/interpret.ml
new file mode 100644
index 00000000..c7eb7415
--- /dev/null
+++ b/Kharisov/lib/interpret.ml
@@ -0,0 +1,159 @@
+[@@@ocaml.text "/*"]
+
+(** Copyright 2021-2024, Kakadu and contributors *)
+
+(** SPDX-License-Identifier: LGPL-3.0-or-later *)
+
+[@@@ocaml.text "/*"]
+
+open Ast
+
+type error =
+ | Parse_error of string
+ | Unbound_variable of string
+ | Division_by_zero
+ | Not_a_function
+ | Type_error of string
+ | Steps_exceeded
+
+let format_error = function
+ | Parse_error _ -> "Parse error"
+ | Unbound_variable x -> "Error: unbound variable " ^ x
+ | Division_by_zero -> "Error: division by zero"
+ | Not_a_function -> "Error: not a function"
+ | Type_error msg -> "Error: " ^ msg
+ | Steps_exceeded -> "Error: step limit exceeded"
+;;
+
+type state =
+ { steps : int (** remaining evaluation steps *)
+ ; output : string list (** accumulated output lines in reverse order *)
+ }
+
+type 'a t = state -> ('a * state, error) result
+
+let return (x : 'a) : 'a t = fun st -> Ok (x, st)
+
+let ( let* ) (m : 'a t) (f : 'a -> 'b t) : 'b t =
+ fun st ->
+ match m st with
+ | Error e -> Error e
+ | Ok (x, st') -> f x st'
+;;
+
+let fail (e : error) : 'a t = fun _st -> Error e
+
+let tick : unit t =
+ fun st ->
+ if st.steps <= 0 then Error Steps_exceeded else Ok ((), { st with steps = st.steps - 1 })
+;;
+
+let emit (line : string) : unit t =
+ fun st -> Ok ((), { st with output = line :: st.output })
+;;
+
+let lift (r : ('a, error) result) : 'a t =
+ fun st ->
+ match r with
+ | Ok x -> Ok (x, st)
+ | Error e -> Error e
+;;
+
+type value =
+ | VInt of int
+ | VClosure of id * expr * env
+ | VBuiltin of (value -> value t)
+
+and env = (id * value) list
+
+let pp_value fmt = function
+ | VInt n -> Format.fprintf fmt "%d" n
+ | VClosure _ -> Format.fprintf fmt ""
+ | VBuiltin _ -> Format.fprintf fmt ""
+;;
+
+let format_value = function
+ | VInt n -> string_of_int n
+ | VClosure _ | VBuiltin _ -> ""
+;;
+
+let run_eval (steps : int) (m : 'a t) : ('a * string list, error) result =
+ match m { steps; output = [] } with
+ | Ok (x, st) -> Ok (x, List.rev st.output)
+ | Error e -> Error e
+;;
+
+let eval_binop op a b : (int, error) result =
+ let bool i = if i then 1 else 0 in
+ match op with
+ | Add -> Ok (a + b)
+ | Sub -> Ok (a - b)
+ | Mul -> Ok (a * b)
+ | Div -> if b = 0 then Error Division_by_zero else Ok (a / b)
+ | Eq -> Ok (bool (a = b))
+ | Neq -> Ok (bool (a <> b))
+ | Lt -> Ok (bool (a < b))
+ | Le -> Ok (bool (a <= b))
+ | Gt -> Ok (bool (a > b))
+ | Ge -> Ok (bool (a >= b))
+;;
+
+let lookup env x =
+ match List.assoc_opt x env with
+ | Some v -> return v
+ | None -> fail (Unbound_variable x)
+;;
+
+let require_int = function
+ | VInt n -> return n
+ | _ -> fail (Type_error "expected an integer")
+;;
+
+let print_builtin v =
+ let* n = require_int v in
+ let* () = emit (string_of_int n) in
+ return (VInt 0)
+;;
+
+let initial_env : env = [ "print", VBuiltin print_builtin ]
+
+let rec eval env expr =
+ let* () = tick in
+ match expr with
+ | EConst n -> return (VInt n)
+ | EVar x -> lookup env x
+ | EFun (x, body) -> return (VClosure (x, body, env))
+ | EBinop (op, e1, e2) ->
+ let* v1 = eval env e1 in
+ let* a = require_int v1 in
+ let* v2 = eval env e2 in
+ let* b = require_int v2 in
+ let* n = lift (eval_binop op a b) in
+ return (VInt n)
+ | EIf (cond, e1, e2) ->
+ let* vc = eval env cond in
+ let* n = require_int vc in
+ if n <> 0 then eval env e1 else eval env e2
+ | EApp (f_expr, arg_expr) ->
+ let* fv = eval env f_expr in
+ let* argv = eval env arg_expr in
+ (match fv with
+ | VClosure (x, body, clo_env) -> eval ((x, argv) :: clo_env) body
+ | VBuiltin f -> f argv
+ | VInt _ -> fail Not_a_function)
+ | ELet (NonRec, x, e1, e2) ->
+ let* v1 = eval env e1 in
+ eval ((x, v1) :: env) e2
+ | ELet (Rec, f, e1, e2) ->
+ (match e1 with
+ | EFun (x, body) ->
+ let rec env' = (f, VClosure (x, body, env')) :: env in
+ eval env' e2
+ | _ -> fail (Type_error "let rec requires a function on the right-hand side"))
+;;
+
+let run ?(steps = 10_000) (src : string) : (value * string list, error) result =
+ match Parser.parse src with
+ | Error msg -> Error (Parse_error msg)
+ | Ok ast -> run_eval steps (eval initial_env ast)
+;;
diff --git a/Kharisov/lib/interpret.mli b/Kharisov/lib/interpret.mli
new file mode 100644
index 00000000..24523b30
--- /dev/null
+++ b/Kharisov/lib/interpret.mli
@@ -0,0 +1,35 @@
+[@@@ocaml.text "/*"]
+
+(** Copyright 2021-2024, Kakadu and contributors *)
+
+(** SPDX-License-Identifier: LGPL-3.0-or-later *)
+
+[@@@ocaml.text "/*"]
+
+type error =
+ | Parse_error of string
+ | Unbound_variable of string
+ | Division_by_zero
+ | Not_a_function
+ | Type_error of string
+ | Steps_exceeded
+
+type state =
+ { steps : int
+ ; output : string list
+ }
+
+type 'a t = state -> ('a * state, error) result
+
+type value =
+ | VInt of int
+ | VClosure of Ast.id * Ast.expr * env
+ | VBuiltin of (value -> value t)
+
+and env = (Ast.id * value) list
+
+val return : 'a -> 'a t
+val pp_value : Format.formatter -> value -> unit
+val format_value : value -> string
+val format_error : error -> string
+val run : ?steps:int -> string -> (value * string list, error) result
diff --git a/Kharisov/lib/parser.ml b/Kharisov/lib/parser.ml
new file mode 100644
index 00000000..05292cd7
--- /dev/null
+++ b/Kharisov/lib/parser.ml
@@ -0,0 +1,166 @@
+[@@@ocaml.text "/*"]
+
+(** Copyright 2021-2024, Kakadu and contributors *)
+
+(** SPDX-License-Identifier: LGPL-3.0-or-later *)
+
+[@@@ocaml.text "/*"]
+
+open Angstrom
+open Ast
+
+let is_ws = function
+ | ' ' | '\t' | '\n' | '\r' -> true
+ | _ -> false
+;;
+
+let is_ident_char = function
+ | 'a' .. 'z' | 'A' .. 'Z' | '0' .. '9' | '_' | '\'' -> true
+ | _ -> false
+;;
+
+let ws = skip_while is_ws
+let token p = ws *> p <* ws
+let parens p = token (char '(') *> p <* token (char ')')
+let symbol s = token (string s)
+
+let keyword k =
+ token
+ (string k
+ >>= fun _ ->
+ peek_char
+ >>= function
+ | Some c when is_ident_char c -> fail "not a keyword boundary"
+ | _ -> return ())
+;;
+
+let is_keyword = function
+ | "let" | "rec" | "in" | "if" | "then" | "else" | "fun" | "true" | "false" -> true
+ | _ -> false
+;;
+
+let ident =
+ token
+ (let* c =
+ satisfy (function
+ | 'a' .. 'z' | '_' -> true
+ | _ -> false)
+ in
+ let* rest = take_while is_ident_char in
+ let name = String.make 1 c ^ rest in
+ if is_keyword name then fail "identifier is a keyword" else return name)
+;;
+
+let digits =
+ token
+ (let* s =
+ take_while1 (function
+ | '0' .. '9' -> true
+ | _ -> false)
+ in
+ let* () =
+ peek_char
+ >>= function
+ | Some c when is_ident_char c -> fail "digit followed by letter"
+ | _ -> return ()
+ in
+ match int_of_string_opt s with
+ | Some n -> return n
+ | None -> fail "integer literal overflow")
+;;
+
+let integer = digits >>| fun n -> EConst n
+
+(* stolen from Angstrom README, only God knows who could create that *)
+let chainl1 e op =
+ let rec go acc = lift2 (fun f x -> f acc x) op e >>= go <|> return acc in
+ e >>= go
+;;
+
+let expr =
+ fix (fun expr ->
+ let atom =
+ choice
+ [ parens expr
+ ; keyword "true" *> return (EConst 1)
+ ; keyword "false" *> return (EConst 0)
+ ; integer
+ ; (ident >>| fun x -> EVar x)
+ ]
+ in
+ let app =
+ let* f = atom in
+ let* args = many atom in
+ return (List.fold_left (fun acc a -> EApp (acc, a)) f args)
+ in
+ let unary =
+ let neg_literal = digits >>| fun n -> EConst (-n) in
+ let neg_expr = app >>| fun e -> EBinop (Sub, EConst 0, e) in
+ token (char '-') *> (neg_literal <|> neg_expr) <|> app
+ in
+ let mul_div =
+ let op =
+ symbol "*" *> return (fun a b -> EBinop (Mul, a, b))
+ <|> symbol "/" *> return (fun a b -> EBinop (Div, a, b))
+ in
+ chainl1 unary op
+ in
+ let add_sub =
+ let op =
+ symbol "+" *> return (fun a b -> EBinop (Add, a, b))
+ <|> symbol "-" *> return (fun a b -> EBinop (Sub, a, b))
+ in
+ chainl1 mul_div op
+ in
+ let comparison =
+ let* lhs = add_sub in
+ let cmp_op =
+ choice
+ [ symbol "<>" *> return Neq
+ ; symbol "<=" *> return Le
+ ; symbol ">=" *> return Ge
+ ; symbol "<" *> return Lt
+ ; symbol ">" *> return Gt
+ ; symbol "=" *> return Eq
+ ]
+ in
+ (let* op = cmp_op in
+ let* rhs = add_sub in
+ return (EBinop (op, lhs, rhs)))
+ <|> return lhs
+ in
+ let param = parens ident <|> ident in
+ let fun_expr =
+ let* _ = keyword "fun" in
+ let* params = many1 param in
+ let* _ = symbol "->" in
+ let* body = expr in
+ return (List.fold_right (fun p acc -> EFun (p, acc)) params body)
+ in
+ let let_expr =
+ let* _ = keyword "let" in
+ let* rf = keyword "rec" *> return Rec <|> return NonRec in
+ let* name = parens ident <|> ident in
+ let* params = many param in
+ let* _ = symbol "=" in
+ let* rhs = expr in
+ let* _ = keyword "in" in
+ let* body = expr in
+ let rhs = List.fold_right (fun p acc -> EFun (p, acc)) params rhs in
+ return (ELet (rf, name, rhs, body))
+ in
+ let if_expr =
+ let* _ = keyword "if" in
+ let* cond = expr in
+ let* _ = keyword "then" in
+ let* e1 = expr in
+ let* _ = keyword "else" in
+ let* e2 = expr in
+ return (EIf (cond, e1, e2))
+ in
+ choice [ let_expr; if_expr; fun_expr; comparison ])
+;;
+
+let parse (s : string) : (expr, string) result =
+ Angstrom.parse_string ~consume:Consume.All (ws *> expr <* ws <* end_of_input) s
+;;
diff --git a/Kharisov/lib/parser.mli b/Kharisov/lib/parser.mli
new file mode 100644
index 00000000..c9c0bb9f
--- /dev/null
+++ b/Kharisov/lib/parser.mli
@@ -0,0 +1,9 @@
+[@@@ocaml.text "/*"]
+
+(** Copyright 2021-2024, Kakadu and contributors *)
+
+(** SPDX-License-Identifier: LGPL-3.0-or-later *)
+
+[@@@ocaml.text "/*"]
+
+val parse : string -> (Ast.expr, string) result
diff --git a/Kharisov/lib/pprint.ml b/Kharisov/lib/pprint.ml
new file mode 100644
index 00000000..0a97dd08
--- /dev/null
+++ b/Kharisov/lib/pprint.ml
@@ -0,0 +1,41 @@
+[@@@ocaml.text "/*"]
+
+(** Copyright 2021-2024, Kakadu and contributors *)
+
+(** SPDX-License-Identifier: LGPL-3.0-or-later *)
+
+[@@@ocaml.text "/*"]
+
+open Ast
+
+let pp_binop fmt = function
+ | Add -> Format.fprintf fmt "+"
+ | Sub -> Format.fprintf fmt "-"
+ | Mul -> Format.fprintf fmt "*"
+ | Div -> Format.fprintf fmt "/"
+ | Eq -> Format.fprintf fmt "="
+ | Neq -> Format.fprintf fmt "<>"
+ | Lt -> Format.fprintf fmt "<"
+ | Le -> Format.fprintf fmt "<="
+ | Gt -> Format.fprintf fmt ">"
+ | Ge -> Format.fprintf fmt ">="
+;;
+
+let pp_rec_flag fmt = function
+ | Rec -> Format.fprintf fmt "rec "
+ | NonRec -> ()
+;;
+
+let rec pp fmt = function
+ | EConst n when n < 0 -> Format.fprintf fmt "(%d)" n
+ | EConst n -> Format.fprintf fmt "%d" n
+ | EVar x -> Format.fprintf fmt "%s" x
+ | EBinop (op, l, r) -> Format.fprintf fmt "(%a %a %a)" pp l pp_binop op pp r
+ | EIf (c, t, e) -> Format.fprintf fmt "(if %a then %a else %a)" pp c pp t pp e
+ | EFun (x, body) -> Format.fprintf fmt "(fun %s -> %a)" x pp body
+ | EApp (f, arg) -> Format.fprintf fmt "(%a %a)" pp f pp arg
+ | ELet (rf, x, e1, e2) ->
+ Format.fprintf fmt "(let %a%s = %a in %a)" pp_rec_flag rf x pp e1 pp e2
+;;
+
+let to_string e = Format.asprintf "%a" pp e
diff --git a/Kharisov/lib/pprint.mli b/Kharisov/lib/pprint.mli
new file mode 100644
index 00000000..a6ab81ed
--- /dev/null
+++ b/Kharisov/lib/pprint.mli
@@ -0,0 +1,10 @@
+[@@@ocaml.text "/*"]
+
+(** Copyright 2021-2024, Kakadu and contributors *)
+
+(** SPDX-License-Identifier: LGPL-3.0-or-later *)
+
+[@@@ocaml.text "/*"]
+
+val pp : Format.formatter -> Ast.expr -> unit
+val to_string : Ast.expr -> string
diff --git a/Kharisov/tests/dune b/Kharisov/tests/dune
new file mode 100644
index 00000000..19e97aaf
--- /dev/null
+++ b/Kharisov/tests/dune
@@ -0,0 +1,20 @@
+(test
+ (name parser_qcheck)
+ (libraries interpret_lib qcheck)
+ (modules parser_qcheck)
+ (instrumentation
+ (backend bisect_ppx)))
+
+(library
+ (name expect_tests)
+ (libraries interpret_lib)
+ (modules parser_expect interpret_expect)
+ (inline_tests)
+ (instrumentation
+ (backend bisect_ppx))
+ (preprocess
+ (pps ppx_expect)))
+
+(cram
+ (applies_to interpret_tests)
+ (deps ../bin/REPL.exe))
diff --git a/Kharisov/tests/interpret_expect.ml b/Kharisov/tests/interpret_expect.ml
new file mode 100644
index 00000000..38993c62
--- /dev/null
+++ b/Kharisov/tests/interpret_expect.ml
@@ -0,0 +1,288 @@
+[@@@ocaml.text "/*"]
+
+(** Copyright 2021-2024, Kakadu and contributors *)
+
+(** SPDX-License-Identifier: LGPL-3.0-or-later *)
+
+[@@@ocaml.text "/*"]
+
+open Interpret_lib
+
+let eval ?(steps = 10_000) src =
+ match Interpret.run ~steps src with
+ | Ok (v, output) ->
+ List.iter print_endline output;
+ print_endline (Interpret.format_value v)
+ | Error e -> print_endline (Interpret.format_error e)
+;;
+
+let%expect_test "integer literal" =
+ eval "42";
+ [%expect {| 42 |}]
+;;
+
+let%expect_test "arithmetic precedence" =
+ eval "2 + 3 * 4";
+ [%expect {| 14 |}]
+;;
+
+let%expect_test "parenthesised expression" =
+ eval "(2 + 3) * 4";
+ [%expect {| 20 |}]
+;;
+
+let%expect_test "unary minus" =
+ eval "-5 + 2";
+ [%expect {| -3 |}]
+;;
+
+let%expect_test "comparisons yield ints" =
+ eval "3 < 5";
+ [%expect {| 1 |}];
+ eval "5 < 3";
+ [%expect {| 0 |}]
+;;
+
+let%expect_test "neq operator" =
+ eval "3 <> 5";
+ [%expect {| 1 |}];
+ eval "3 <> 3";
+ [%expect {| 0 |}]
+;;
+
+let%expect_test "le operator" =
+ eval "3 <= 5";
+ [%expect {| 1 |}];
+ eval "5 <= 3";
+ [%expect {| 0 |}]
+;;
+
+let%expect_test "gt operator" =
+ eval "5 > 3";
+ [%expect {| 1 |}];
+ eval "3 > 5";
+ [%expect {| 0 |}]
+;;
+
+let%expect_test "ge operator" =
+ eval "5 >= 5";
+ [%expect {| 1 |}];
+ eval "3 >= 5";
+ [%expect {| 0 |}]
+;;
+
+let%expect_test "let binding" =
+ eval "let x = 10 in x + 7";
+ [%expect {| 17 |}]
+;;
+
+let%expect_test "shadowing" =
+ eval "let x = 1 in let x = 2 in x + 10";
+ [%expect {| 12 |}]
+;;
+
+let%expect_test "closures capture environment" =
+ eval {|
+ let x = 10 in
+ let f = fun y -> x + y in
+ let x = 100 in
+ f 5
+ |};
+ [%expect {| 15 |}]
+;;
+
+let%expect_test "lambda application" =
+ eval "(fun x -> x + 1) 5";
+ [%expect {| 6 |}]
+;;
+
+let%expect_test "multi-argument sugar" =
+ eval "let add = fun x y -> x + y in add 3 4";
+ [%expect {| 7 |}]
+;;
+
+let%expect_test "partial application" =
+ eval "let add x y = x + y in let add5 = add 5 in add5 3 + add5 2";
+ [%expect {| 15 |}]
+;;
+
+let%expect_test "higher-order function" =
+ eval "let apply_twice f x = f (f x) in let inc x = x + 1 in apply_twice inc 0";
+ [%expect {| 2 |}]
+;;
+
+let%expect_test "returning a function prints " =
+ eval "fun x -> x";
+ [%expect {| |}]
+;;
+
+let%expect_test "factorial" =
+ eval "let rec fact n = if n = 0 then 1 else n * fact (n - 1) in fact 5";
+ [%expect {| 120 |}]
+;;
+
+let%expect_test "fibonacci" =
+ eval
+ {|
+ let rec fib n =
+ if n = 0 then 0
+ else if n = 1 then 1
+ else fib (n - 1) + fib (n - 2)
+ in fib 10
+ |};
+ [%expect {| 55 |}]
+;;
+
+let%expect_test "print side-effect and value" =
+ eval "let _ = print 42 in 0";
+ [%expect {|
+ 42
+ 0 |}]
+;;
+
+let%expect_test "multiple prints" =
+ eval "let _ = print 1 in let _ = print 2 in 3";
+ [%expect {|
+ 1
+ 2
+ 3 |}]
+;;
+
+let%expect_test "infinite loop hits step limit" =
+ eval ~steps:50 "let rec loop x = loop x in loop 1";
+ [%expect {| Error: step limit exceeded |}]
+;;
+
+let%expect_test "factorial with tight limit" =
+ eval ~steps:20 "let rec fact n = if n = 0 then 1 else n * fact (n - 1) in fact 10";
+ [%expect {| Error: step limit exceeded |}]
+;;
+
+let%expect_test "factorial with enough steps" =
+ eval ~steps:5000 "let rec fact n = if n = 0 then 1 else n * fact (n - 1) in fact 10";
+ [%expect {| 3628800 |}]
+;;
+
+let%expect_test "unbound variable" =
+ eval "x + 1";
+ [%expect {| Error: unbound variable x |}]
+;;
+
+let%expect_test "not a function" =
+ eval "5 3";
+ [%expect {| Error: not a function |}]
+;;
+
+let%expect_test "division by zero" =
+ eval "10 / 0";
+ [%expect {| Error: division by zero |}]
+;;
+
+let%expect_test "if condition is not int" =
+ eval "if fun x -> x then 1 else 2";
+ [%expect {| Error: expected an integer |}]
+;;
+
+let%expect_test "binop on non-int" =
+ eval "1 + (fun x -> x)";
+ [%expect {| Error: expected an integer |}]
+;;
+
+let%expect_test "print non-int" =
+ eval "print (fun x -> x)";
+ [%expect {| Error: expected an integer |}]
+;;
+
+let%expect_test "let rec with non-function" =
+ eval "let rec x = 1 in x";
+ [%expect {| Error: let rec requires a function on the right-hand side |}]
+;;
+
+let%expect_test "parse error" =
+ eval "let x = in 5";
+ [%expect {| Parse error |}]
+;;
+
+let%expect_test "pp_value for integers" =
+ Format.printf "%a" Interpret.pp_value (Interpret.VInt 99);
+ [%expect {| 99 |}]
+;;
+
+let%expect_test "pp_value for closure" =
+ Format.printf "%a" Interpret.pp_value (Interpret.VClosure ("x", Ast.EVar "x", []));
+ [%expect {| |}]
+;;
+
+let%expect_test "pp_value for builtin" =
+ Format.printf
+ "%a"
+ Interpret.pp_value
+ (Interpret.VBuiltin (fun _ -> Interpret.return (Interpret.VInt 0)));
+ [%expect {| |}]
+;;
+
+let%expect_test "format_value for closure" =
+ print_endline (Interpret.format_value (Interpret.VClosure ("x", Ast.EVar "x", [])));
+ [%expect {| |}]
+;;
+
+let%expect_test "format_value for builtin" =
+ print_endline
+ (Interpret.format_value
+ (Interpret.VBuiltin (fun _ -> Interpret.return (Interpret.VInt 0))));
+ [%expect {| |}]
+;;
+
+let%expect_test "pprint negative constant" =
+ print_endline (Pprint.to_string (Ast.EConst (-5)));
+ [%expect {| (-5) |}]
+;;
+
+let%expect_test "factorial via fix combinator" =
+ eval
+ {|
+ let fix = fun f ->
+ (fun x -> f (fun v -> x x v)) (fun x -> f (fun v -> x x v))
+ in
+ let fact = fix (fun self -> fun n ->
+ if n = 0 then 1 else n * self (n - 1))
+ in
+ fact 5
+ |};
+ [%expect {| 120 |}]
+;;
+
+let%expect_test "fibonacci via fix combinator" =
+ eval
+ {|
+ let fix = fun f ->
+ (fun x -> f (fun v -> x x v)) (fun x -> f (fun v -> x x v))
+ in
+ let fib = fix (fun self -> fun n ->
+ if n = 0 then 0
+ else if n = 1 then 1
+ else self (n - 1) + self (n - 2))
+ in
+ fib 10
+ |};
+ [%expect {| 55 |}]
+;;
+
+let%expect_test "shadow builtin print" =
+ eval "let print = fun x -> x + 1 in print 5";
+ [%expect {| 6 |}]
+;;
+
+let%expect_test "shadow builtin print restores after scope" =
+ eval
+ {|
+ let _ =
+ let print = fun x -> x * 2 in
+ print 10
+ in
+ let _ = print 42 in 0
+ |};
+ [%expect {|
+ 42
+ 0 |}]
+;;
diff --git a/Kharisov/tests/interpret_expect.mli b/Kharisov/tests/interpret_expect.mli
new file mode 100644
index 00000000..c1135e06
--- /dev/null
+++ b/Kharisov/tests/interpret_expect.mli
@@ -0,0 +1,7 @@
+[@@@ocaml.text "/*"]
+
+(** Copyright 2021-2024, Kakadu and contributors *)
+
+(** SPDX-License-Identifier: LGPL-3.0-or-later *)
+
+[@@@ocaml.text "/*"]
diff --git a/Kharisov/tests/interpret_tests.t b/Kharisov/tests/interpret_tests.t
new file mode 100644
index 00000000..69031a0b
--- /dev/null
+++ b/Kharisov/tests/interpret_tests.t
@@ -0,0 +1,298 @@
+Copyright 2021-2024, Kakadu and contributors
+SPDX-License-Identifier: CC0-1.0
+
+ $ ../bin/REPL.exe <<'EOF'
+ > 42
+ > EOF
+ 42
+
+ $ ../bin/REPL.exe <<'EOF'
+ > 0
+ > EOF
+ 0
+
+ $ ../bin/REPL.exe <<'EOF'
+ > 2 + 3
+ > EOF
+ 5
+
+ $ ../bin/REPL.exe <<'EOF'
+ > 10 - 4
+ > EOF
+ 6
+
+ $ ../bin/REPL.exe <<'EOF'
+ > 6 * 7
+ > EOF
+ 42
+
+ $ ../bin/REPL.exe <<'EOF'
+ > 15 / 3
+ > EOF
+ 5
+
+ $ ../bin/REPL.exe <<'EOF'
+ > 2 + 3 * 4
+ > EOF
+ 14
+
+ $ ../bin/REPL.exe <<'EOF'
+ > (2 + 3) * 4
+ > EOF
+ 20
+
+ $ ../bin/REPL.exe <<'EOF'
+ > 10 - 3 - 2
+ > EOF
+ 5
+
+ $ ../bin/REPL.exe <<'EOF'
+ > 8 / 2 / 2
+ > EOF
+ 2
+
+ $ ../bin/REPL.exe <<'EOF'
+ > -5 + 3
+ > EOF
+ -2
+
+ $ ../bin/REPL.exe <<'EOF'
+ > -(2 + 3) * 4
+ > EOF
+ -20
+
+ $ ../bin/REPL.exe <<'EOF'
+ > 5 = 5
+ > EOF
+ 1
+
+ $ ../bin/REPL.exe <<'EOF'
+ > 5 <> 3
+ > EOF
+ 1
+
+ $ ../bin/REPL.exe <<'EOF'
+ > 3 < 5
+ > EOF
+ 1
+
+ $ ../bin/REPL.exe <<'EOF'
+ > 5 <= 5
+ > EOF
+ 1
+
+ $ ../bin/REPL.exe <<'EOF'
+ > 5 > 3
+ > EOF
+ 1
+
+ $ ../bin/REPL.exe <<'EOF'
+ > 5 >= 5
+ > EOF
+ 1
+
+ $ ../bin/REPL.exe <<'EOF'
+ > if 1 then 10 else 20
+ > EOF
+ 10
+
+ $ ../bin/REPL.exe <<'EOF'
+ > if 0 then 10 else 20
+ > EOF
+ 20
+
+ $ ../bin/REPL.exe <<'EOF'
+ > if 2 = 2 then 1 else 0
+ > EOF
+ 1
+
+ $ ../bin/REPL.exe <<'EOF'
+ > if true then 100 else 200
+ > EOF
+ 100
+
+ $ ../bin/REPL.exe <<'EOF'
+ > if false then 100 else 200
+ > EOF
+ 200
+
+ $ ../bin/REPL.exe <<'EOF'
+ > let x = 10 in x + 7
+ > EOF
+ 17
+
+ $ ../bin/REPL.exe <<'EOF'
+ > let x = 1 in let x = 2 in x + 10
+ > EOF
+ 12
+
+ $ ../bin/REPL.exe <<'EOF'
+ > let x = 3 in let y = 4 in x * y + 1
+ > EOF
+ 13
+
+ $ ../bin/REPL.exe <<'EOF'
+ > (fun x -> x + 1) 5
+ > EOF
+ 6
+
+ $ ../bin/REPL.exe <<'EOF'
+ > let add = fun x y -> x + y in add 3 4
+ > EOF
+ 7
+
+ $ ../bin/REPL.exe <<'EOF'
+ > let add x y = x + y in add 3 4
+ > EOF
+ 7
+
+ $ ../bin/REPL.exe <<'EOF'
+ > let x = 10 in
+ > let f = fun y -> x + y in
+ > let x = 100 in
+ > f 5
+ > EOF
+ 15
+
+ $ ../bin/REPL.exe <<'EOF'
+ > let apply_twice f x = f (f x) in
+ > let inc x = x + 1 in
+ > apply_twice inc 5
+ > EOF
+ 7
+
+ $ ../bin/REPL.exe <<'EOF'
+ > let add x y = x + y in let add5 = add 5 in add5 3 + add5 2
+ > EOF
+ 15
+
+ $ ../bin/REPL.exe <<'EOF'
+ > let rec fact n = if n = 0 then 1 else n * fact (n - 1) in fact 5
+ > EOF
+ 120
+
+ $ ../bin/REPL.exe <<'EOF'
+ > let rec fib n =
+ > if n = 0 then 0
+ > else if n = 1 then 1
+ > else fib (n - 1) + fib (n - 2)
+ > in fib 10
+ > EOF
+ 55
+
+ $ ../bin/REPL.exe <<'EOF'
+ > let rec sum n = if n = 0 then 0 else n + sum (n - 1) in sum 100
+ > EOF
+ 5050
+
+ $ ../bin/REPL.exe <<'EOF'
+ > let _ = print 42 in 0
+ > EOF
+ 42
+ 0
+
+ $ ../bin/REPL.exe <<'EOF'
+ > let _ = print 1 in let _ = print 2 in 3
+ > EOF
+ 1
+ 2
+ 3
+
+ $ ../bin/REPL.exe <<'EOF'
+ > let _ = print (2 + 3 * 4) in 0
+ > EOF
+ 14
+ 0
+
+ $ ../bin/REPL.exe 50 <<'EOF' 2>&1
+ > let rec loop x = loop x in loop 1
+ > EOF
+ Error: step limit exceeded
+ [1]
+
+ $ ../bin/REPL.exe <<'EOF' 2>&1
+ > x + 1
+ > EOF
+ Error: unbound variable x
+ [1]
+
+ $ ../bin/REPL.exe <<'EOF' 2>&1
+ > 5 3
+ > EOF
+ Error: not a function
+ [1]
+
+ $ ../bin/REPL.exe <<'EOF' 2>&1
+ > 10 / 0
+ > EOF
+ Error: division by zero
+ [1]
+
+ $ ../bin/REPL.exe <<'EOF' 2>&1
+ > let x = in 5
+ > EOF
+ Parse error
+ [1]
+
+ $ ../bin/REPL.exe <<'EOF' 2>&1
+ > if fun x -> x then 1 else 2
+ > EOF
+ Error: expected an integer
+ [1]
+
+ $ ../bin/REPL.exe <<'EOF' 2>&1
+ > 1 + (fun x -> x)
+ > EOF
+ Error: expected an integer
+ [1]
+
+ $ ../bin/REPL.exe <<'EOF' 2>&1
+ > print (fun x -> x)
+ > EOF
+ Error: expected an integer
+ [1]
+
+ $ ../bin/REPL.exe <<'EOF' 2>&1
+ > let rec x = 1 in x
+ > EOF
+ Error: let rec requires a function on the right-hand side
+ [1]
+
+ $ ../bin/REPL.exe <<'EOF'
+ > let fix = fun f ->
+ > (fun x -> f (fun v -> x x v)) (fun x -> f (fun v -> x x v))
+ > in
+ > let fact = fix (fun self -> fun n ->
+ > if n = 0 then 1 else n * self (n - 1))
+ > in
+ > fact 5
+ > EOF
+ 120
+
+ $ ../bin/REPL.exe <<'EOF'
+ > let fix = fun f ->
+ > (fun x -> f (fun v -> x x v)) (fun x -> f (fun v -> x x v))
+ > in
+ > let fib = fix (fun self -> fun n ->
+ > if n = 0 then 0
+ > else if n = 1 then 1
+ > else self (n - 1) + self (n - 2))
+ > in
+ > fib 10
+ > EOF
+ 55
+
+ $ ../bin/REPL.exe <<'EOF'
+ > let print = fun x -> x + 1 in print 5
+ > EOF
+ 6
+
+ $ ../bin/REPL.exe <<'EOF'
+ > let _ =
+ > let print = fun x -> x * 2 in
+ > print 10
+ > in
+ > let _ = print 42 in 0
+ > EOF
+ 42
+ 0
diff --git a/Kharisov/tests/parser_expect.ml b/Kharisov/tests/parser_expect.ml
new file mode 100644
index 00000000..6f0b1b33
--- /dev/null
+++ b/Kharisov/tests/parser_expect.ml
@@ -0,0 +1,197 @@
+[@@@ocaml.text "/*"]
+
+(** Copyright 2021-2024, Kakadu and contributors *)
+
+(** SPDX-License-Identifier: LGPL-3.0-or-later *)
+
+[@@@ocaml.text "/*"]
+
+open Interpret_lib
+
+let show s =
+ match Parser.parse s with
+ | Ok e -> print_endline (Pprint.to_string e)
+ | Error msg -> print_endline ("Parse error: " ^ msg)
+;;
+
+let%expect_test "integer" =
+ show "42";
+ [%expect {| 42 |}]
+;;
+
+let%expect_test "integer with whitespace" =
+ show " 0 ";
+ [%expect {| 0 |}]
+;;
+
+let%expect_test "variable" =
+ show "x";
+ [%expect {| x |}]
+;;
+
+let%expect_test "true/false sugar" =
+ show "true";
+ [%expect {| 1 |}];
+ show "false";
+ [%expect {| 0 |}]
+;;
+
+let%expect_test "addition" =
+ show "1 + 2";
+ [%expect {| (1 + 2) |}]
+;;
+
+let%expect_test "mul before add" =
+ show "1 + 2 * 3";
+ [%expect {| (1 + (2 * 3)) |}]
+;;
+
+let%expect_test "parentheses override precedence" =
+ show "(1 + 2) * 3";
+ [%expect {| ((1 + 2) * 3) |}]
+;;
+
+let%expect_test "left-associative subtraction" =
+ show "10 - 3 - 2";
+ [%expect {| ((10 - 3) - 2) |}]
+;;
+
+let%expect_test "left-associative division" =
+ show "8 / 2 / 2";
+ [%expect {| ((8 / 2) / 2) |}]
+;;
+
+let%expect_test "complex arithmetic" =
+ show "1 + 2 * 3 - 4 / 2";
+ [%expect {| ((1 + (2 * 3)) - (4 / 2)) |}]
+;;
+
+let%expect_test "unary minus" =
+ show "-5 + 3";
+ [%expect {| ((-5) + 3) |}]
+;;
+
+let%expect_test "eq" =
+ show "x = 5";
+ [%expect {| (x = 5) |}]
+;;
+
+let%expect_test "neq" =
+ show "x <> 0";
+ [%expect {| (x <> 0) |}]
+;;
+
+let%expect_test "lt le gt ge" =
+ show "a < b";
+ [%expect {| (a < b) |}];
+ show "a <= b";
+ [%expect {| (a <= b) |}];
+ show "a > b";
+ [%expect {| (a > b) |}];
+ show "a >= b";
+ [%expect {| (a >= b) |}]
+;;
+
+let%expect_test "comparison with arithmetic" =
+ show "a * b <= c + d";
+ [%expect {| ((a * b) <= (c + d)) |}]
+;;
+
+let%expect_test "lambda" =
+ show "fun x -> x + 1";
+ [%expect {| (fun x -> (x + 1)) |}]
+;;
+
+let%expect_test "multi-arg lambda sugar" =
+ show "fun x y z -> x";
+ [%expect {| (fun x -> (fun y -> (fun z -> x))) |}]
+;;
+
+let%expect_test "application" =
+ show "f x";
+ [%expect {| (f x) |}]
+;;
+
+let%expect_test "nested application (left-assoc)" =
+ show "f x y z";
+ [%expect {| (((f x) y) z) |}]
+;;
+
+let%expect_test "application of complex arg" =
+ show "f (x + 1)";
+ [%expect {| (f (x + 1)) |}]
+;;
+
+let%expect_test "let" =
+ show "let x = 5 in x + 1";
+ [%expect {| (let x = 5 in (x + 1)) |}]
+;;
+
+let%expect_test "let with function sugar" =
+ show "let f x y = x + y in f 1 2";
+ [%expect {| (let f = (fun x -> (fun y -> (x + y))) in ((f 1) 2)) |}]
+;;
+
+let%expect_test "let rec" =
+ show "let rec f n = n * f (n - 1) in f 5";
+ [%expect {| (let rec f = (fun n -> (n * (f (n - 1)))) in (f 5)) |}]
+;;
+
+let%expect_test "nested let" =
+ show "let x = 1 in let y = 2 in x + y";
+ [%expect {| (let x = 1 in (let y = 2 in (x + y))) |}]
+;;
+
+let%expect_test "if-then-else" =
+ show "if x = 0 then 1 else 2";
+ [%expect {| (if (x = 0) then 1 else 2) |}]
+;;
+
+let%expect_test "nested if" =
+ show "if x then if y then 1 else 2 else 3";
+ [%expect {| (if x then (if y then 1 else 2) else 3) |}]
+;;
+
+let%expect_test "keyword-like identifiers" =
+ show "let funx = 1 in funx";
+ [%expect {| (let funx = 1 in funx) |}];
+ show "let letx = 1 in letx";
+ [%expect {| (let letx = 1 in letx) |}];
+ show "let ifx = 1 in ifx";
+ [%expect {| (let ifx = 1 in ifx) |}]
+;;
+
+let%expect_test "error: missing rhs in let" =
+ show "let x = in 5";
+ [%expect {| Parse error: : no more choices |}]
+;;
+
+let%expect_test "error: empty input" =
+ show "";
+ [%expect {| Parse error: : no more choices |}]
+;;
+
+let%expect_test "juxtaposition parses as application" =
+ show "1 2 3";
+ [%expect {| ((1 2) 3) |}]
+;;
+
+let%expect_test "digit-letter suffix rejected (e.g., 3x)" =
+ show "3x";
+ [%expect {| Parse error: : no more choices |}]
+;;
+
+let%expect_test "integer overflow" =
+ show "99999999999999999999";
+ [%expect {| Parse error: : no more choices |}]
+;;
+
+let%expect_test "parenthesized identifier in fun" =
+ show "fun (x) -> x";
+ [%expect {| (fun x -> x) |}]
+;;
+
+let%expect_test "parenthesized identifier in let" =
+ show "let (f) x = x in f 5";
+ [%expect {| (let f = (fun x -> x) in (f 5)) |}]
+;;
diff --git a/Kharisov/tests/parser_expect.mli b/Kharisov/tests/parser_expect.mli
new file mode 100644
index 00000000..c1135e06
--- /dev/null
+++ b/Kharisov/tests/parser_expect.mli
@@ -0,0 +1,7 @@
+[@@@ocaml.text "/*"]
+
+(** Copyright 2021-2024, Kakadu and contributors *)
+
+(** SPDX-License-Identifier: LGPL-3.0-or-later *)
+
+[@@@ocaml.text "/*"]
diff --git a/Kharisov/tests/parser_qcheck.ml b/Kharisov/tests/parser_qcheck.ml
new file mode 100644
index 00000000..e4b16522
--- /dev/null
+++ b/Kharisov/tests/parser_qcheck.ml
@@ -0,0 +1,164 @@
+[@@@ocaml.text "/*"]
+
+(** Copyright 2021-2024, Kakadu and contributors *)
+
+(** SPDX-License-Identifier: LGPL-3.0-or-later *)
+
+[@@@ocaml.text "/*"]
+
+open QCheck
+open Interpret_lib
+
+let gen_id = Gen.oneof_list [ "x"; "y"; "z"; "n"; "m"; "f"; "g" ]
+let gen_binop = Gen.oneof_list Ast.[ Add; Sub; Mul; Div; Eq; Neq; Lt; Le; Gt; Ge ]
+let gen_rec_flag = Gen.oneof_list Ast.[ Rec; NonRec ]
+
+let rec gen_expr size =
+ if size <= 0
+ then
+ Gen.oneof
+ [ Gen.map (fun n -> Ast.EConst n) Gen.nat_small
+ ; Gen.map (fun x -> Ast.EVar x) gen_id
+ ]
+ else (
+ let smaller = gen_expr (size / 2) in
+ let gen_let =
+ Gen.map3
+ (fun (rf, x) rhs body ->
+ let rhs =
+ match rf with
+ | Ast.Rec ->
+ (match rhs with
+ | Ast.EFun _ -> rhs
+ | _ -> Ast.EFun ("_k", rhs))
+ | Ast.NonRec -> rhs
+ in
+ Ast.ELet (rf, x, rhs, body))
+ (Gen.pair gen_rec_flag gen_id)
+ smaller
+ smaller
+ in
+ Gen.oneof_weighted
+ [ 3, Gen.map (fun n -> Ast.EConst n) Gen.nat_small
+ ; 3, Gen.map (fun x -> Ast.EVar x) gen_id
+ ; 2, Gen.map3 (fun op l r -> Ast.EBinop (op, l, r)) gen_binop smaller smaller
+ ; 1, Gen.map2 (fun x body -> Ast.EFun (x, body)) gen_id smaller
+ ; 1, Gen.map2 (fun f a -> Ast.EApp (f, a)) smaller smaller
+ ; 1, Gen.map3 (fun c t e -> Ast.EIf (c, t, e)) smaller smaller smaller
+ ; 1, gen_let
+ ])
+;;
+
+let arb_expr = make ~print:Pprint.to_string (Gen.sized (fun n -> gen_expr (min n 4)))
+
+let round_trip_test =
+ Test.make ~name:"print ∘ parse ∘ print = print" ~count:300 arb_expr (fun e ->
+ let s = Pprint.to_string e in
+ match Parser.parse s with
+ | Error _ -> false
+ | Ok e' -> String.equal (Pprint.to_string e') s)
+;;
+
+let nonempty_test =
+ Test.make ~name:"print produces non-empty string" ~count:300 arb_expr (fun e ->
+ String.length (Pprint.to_string e) > 0)
+;;
+
+let gen_invalid_program =
+ Gen.oneof_list
+ [ ""
+ ; "let x ="
+ ; "if x then"
+ ; "let rec"
+ ; "fun ->"
+ ; "let = 1 in 2"
+ ; "if then else"
+ ; "+ +"
+ ; "let x = in"
+ ]
+;;
+
+let invalid_program_test =
+ Test.make
+ ~name:"invalid programs are rejected"
+ ~count:100
+ (make gen_invalid_program)
+ (fun s ->
+ match Parser.parse s with
+ | Error _ -> true
+ | Ok _ -> false)
+;;
+
+let no_crash_test =
+ Test.make
+ ~name:"parser never crashes on arbitrary input"
+ ~count:500
+ (make Gen.string)
+ (fun s ->
+ match Parser.parse s with
+ | Ok _ | Error _ -> true)
+;;
+
+let idempotent_test =
+ Test.make
+ ~name:"idempotent: parse∘print∘parse∘print = parse∘print"
+ ~count:300
+ arb_expr
+ (fun e ->
+ let s1 = Pprint.to_string e in
+ match Parser.parse s1 with
+ | Error _ -> false
+ | Ok e1 ->
+ let s2 = Pprint.to_string e1 in
+ (match Parser.parse s2 with
+ | Error _ -> false
+ | Ok e2 -> String.equal (Pprint.to_string e2) s2))
+;;
+
+let int_literal_test =
+ Test.make
+ ~name:"integer literals parse correctly"
+ ~count:300
+ (make ~print:string_of_int Gen.nat_small)
+ (fun n ->
+ let s = string_of_int n in
+ match Parser.parse s with
+ | Error _ -> false
+ | Ok e -> String.equal (Pprint.to_string e) s)
+;;
+
+let var_literal_test =
+ Test.make
+ ~name:"variable names parse correctly"
+ ~count:100
+ (make ~print:Fun.id gen_id)
+ (fun x ->
+ match Parser.parse x with
+ | Error _ -> false
+ | Ok e -> String.equal (Pprint.to_string e) x)
+;;
+
+let neg_int_test =
+ Test.make
+ ~name:"negative integers round-trip exactly"
+ ~count:300
+ (make ~print:string_of_int (Gen.map (fun n -> -(n + 1)) Gen.nat_small))
+ (fun n ->
+ let s = Pprint.to_string (Ast.EConst n) in
+ match Parser.parse s with
+ | Error _ -> false
+ | Ok e' -> String.equal (Pprint.to_string e') s)
+;;
+
+let () =
+ QCheck_runner.run_tests_main
+ [ round_trip_test
+ ; nonempty_test
+ ; invalid_program_test
+ ; no_crash_test
+ ; idempotent_test
+ ; int_literal_test
+ ; var_literal_test
+ ; neg_int_test
+ ]
+;;