grammar,astgen: support unsafe block

bsc/AST.py

@@ -160,13 +160,16 @@ def __str__(self):
         return res
 
 class BlockStmt:
-    def __init__(self, stmts, pos):
+    def __init__(self, is_unsafe, stmts, pos):
+        self.is_unsafe = is_unsafe
         self.stmts = stmts
         self.pos = pos
 
     def __str__(self):
         stmts = '\n'.join([str(stmt) for stmt in self.stmts])
-        return f"{{ {stmts} }}"
+        res = "unsafe " if self.is_unsafe else ""
+        res += f"{{ {stmts} }}"
+        return res
 
 # Expressions
 

bsc/astgen.py

@@ -186,8 +186,12 @@ def block(self, *nodes):
         return list(nodes[1:-1])
 
     def block_stmt(self, *nodes):
-        stmts = list(nodes[1:-1])
-        return BlockStmt(stmts, self.mkpos(nodes[0]) + self.mkpos(nodes[-1]))
+        is_unsafe = nodes[0] != None
+        stmts = list(nodes[2:-1])
+        return BlockStmt(
+            is_unsafe, stmts,
+            self.mkpos(nodes[0]) + self.mkpos(nodes[-1])
+        )
 
     def while_stmt(self, *nodes):
         return WhileStmt(nodes[1], nodes[2], self.mkpos(nodes[0]))

bsc/grammar.lark

@@ -75,7 +75,7 @@ primitive_type: "any"
        | KW_WHILE expr block -> while_stmt
 
 block: LBRACE stmt* RBRACE // returns array of stmts in AstGen
-block_stmt: LBRACE stmt* RBRACE // returns BlockStmt in AstGen
+block_stmt: [KW_UNSAFE] LBRACE stmt* RBRACE // returns BlockStmt in AstGen
 
 assignment: expr (COMMA expr)* op_assign expr
 op_assign: OP_ASSIGN
@@ -214,6 +214,7 @@ KW_PUB.1: "pub"
 KW_SELF.1: "self"
 KW_TRUE.1: "true"
 KW_USE.1: "use"
+KW_UNSAFE.1: "unsafe"
 KW_VAR.1: "var"
 KW_WHILE.1: "while"
 

tests/syntax.bs

@@ -37,6 +37,9 @@ enum WorldLevel {
     undefined = 0xFF
 
     fn from_string(s: string) Self {
+        unsafe {
+            "unsafe!"
+        }
         return match s {
             "overworld" => .overworld,
             "midgard" => .midgard,