Add f-string docs

Author: Folyd

docs/guide/ai/agent.mdx

@@ -281,7 +281,7 @@ agent CustomerSupport {
 
     fn summarize_conversation() -> str {
         let history = conversation_history.join("\n");
-        return prompt "Summarize this conversation: {history}";
+        return prompt f"Summarize this conversation: {history}";
     }
 }
 ```
@@ -296,7 +296,7 @@ agent CodeExpert {
     model: "gpt-4",  // More capable model for coding tasks
 
     fn review_code(code: str) -> str {
-        return prompt "Review this code and provide feedback: {code}";
+        return prompt f"Review this code and provide feedback: {code}";
     }
 }
 

docs/guide/ai/function.md

@@ -21,7 +21,7 @@ You can not use `prompt` outside the non-ai function.
 ```rust
 fn analyze_sentiment(text: str) -> float {
     // [line 3] Error at 'prompt': Can't prompt outside of ai function or root script.
-    let sentiment = prompt "Analyze the sentiment of this text and return a score between -1 and 1: {text}";
+    let sentiment = prompt f"Analyze the sentiment of this text and return a score between -1 and 1: {text}";
     return float(sentiment);
 }
 ```
@@ -34,7 +34,7 @@ Here's a basic example of an AI function that analyzes sentiment in text:
 
 ```rust
 ai fn analyze_sentiment(text: str) -> float {
-    let sentiment = prompt "Analyze the sentiment of this text and return a score between -1 and 1: {text}";
+    let sentiment = prompt f"Analyze the sentiment of this text and return a score between -1 and 1: {text}";
     return float(sentiment);
 }
 
@@ -50,14 +50,14 @@ Since AI functions often involve network operations and third-party services, it
 
 ```rust
 ai fn generate_summary(text: str) -> str | NetworkError! {
-    let summary = prompt "Summarize this text in 2-3 sentences: {text}" ?;
+    let summary = prompt f"Summarize this text in 2-3 sentences: {text}" ?;
     return summary;
 }
 
 // Using the function with error handling
 let article = "...long article text...";
 let summary = generate_summary(article) |err| {
-    print("Failed to generate summary: {err}");
+    print(f"Failed to generate summary: {err}");
     return "Summary unavailable";
 };
 ```
@@ -69,7 +69,7 @@ You can customize the behavior of AI functions by configuring prompt parameters:
 ```rust
 ai fn generate_ideas(topic: str, count: int = 3) -> str {
     let ideas = prompt {
-        input: "Generate {count} creative ideas about {topic}",
+        input: f"Generate {count} creative ideas about {topic}",
         temperature: 0.9,  // Higher creativity
         max_tokens: 300
     };

docs/guide/ai/prompt.mdx

@@ -88,7 +88,7 @@ Like other AIScript operations, you can use error handling with the `prompt` key
 
 ```rust
 let response = prompt "Generate a complex response" |err| {
-    print("Error occurred: {err}");
+    print(f"Error occurred: {err}");
     return "Fallback response";
 };
 ```
@@ -126,13 +126,13 @@ print(poem);
 ```rust
 // Using OpenAI
 let openai_response = prompt {
-    input: "Summarize this article: {article_text}",
+    input: f"Summarize this article: {article_text}",
     model: "gpt-4"
 };
 
 // Using Claude
 let claude_response = prompt {
-    input: "Summarize this article: {article_text}" ,
+    input: f"Summarize this article: {article_text}" ,
     model: "claude-3.7"
 };
 ```
@@ -141,8 +141,8 @@ let claude_response = prompt {
 
 ```rust
 let topic = prompt "Suggest a topic for a blog post";
-let outline = prompt "Create an outline for a blog post about: {topic}";
-let introduction = prompt "Write an introduction for a blog post with this outline: {outline}";
+let outline = prompt f"Create an outline for a blog post about: {topic}";
+let introduction = prompt f"Write an introduction for a blog post with this outline: {outline}";
 
 print("Topic:", topic);
 print("Outline", outline);

docs/guide/contribution/roadmap.md

@@ -4,10 +4,13 @@ Currently, **AIScript** is in its early stages of development. This roadmap outl
 
 ## Language Features
 
-- [ ] **String Interpolation Enhancement**
+- [x] **String Interpolation**
   - Improve the current string interpolation with formatting options
   - Add support for more complex expressions within interpolated strings
 
+- [ ] `for in` Loop
+  - Add support for iterating over arrays and objects
+
 - [ ] **Type System Improvements**
   - Enhance type annotations and static checking
 

docs/guide/language/basic.mdx

@@ -1,4 +1,4 @@
-import { Badge } from 'rspress/theme';
+import { Badge } from "rspress/theme";
 
 # Basic Syntax
 
@@ -56,7 +56,6 @@ if len(global_variable) > 1 {
 
 Constants are declared with the `const` keyword and are immutable. Constants can only be declared once and must be initialized with a value; they cannot be reassigned.
 
-
 ```js
 const PI = 3.14;
 
@@ -94,17 +93,18 @@ let numbers = [1, 2, 3, 4, 5];
 // object literal
 let address_key = "address";
 let person = {
-    "name": "AIScript",
-    age: 18, // double quotes are optional
-    "is_male": true,
-    "hobbies": ["reading", "coding", "gaming"],
-    [address_key]: { // key name are computable
-        "city": "Beijing",
-        "street": "No. 100, Xihuan Road",
-        "zipcode": "100000",
-        "country": "China",
-        "phone": "13800138000",
-    }
+  name: "AIScript",
+  age: 18, // double quotes are optional
+  is_male: true,
+  hobbies: ["reading", "coding", "gaming"],
+  [address_key]: {
+    // key name are computable
+    city: "Beijing",
+    street: "No. 100, Xihuan Road",
+    zipcode: "100000",
+    country: "China",
+    phone: "13800138000",
+  },
 };
 
 //  tuples
@@ -167,13 +167,37 @@ let b = "Hello, {a}!";
 
 // string concatenation
 let a = "AIScript";
-let b = "Hello, " + a + "!";
+let b = "Hello, {a}!";
 
 // string length
 let a = "AIScript";
 print(len(a)); // print 8
 ```
 
+## Formatted String Literal
+
+AIScript supports `f-strings` (formatted string literals, like Python's [f-string](https://docs.python.org/3/tutorial/inputoutput.html#tut-f-strings) but not identical) for string interpolation. F-strings provide a concise and readable way to embed expressions inside string literals. To create an f-string, prefix the string with `f` and use curly braces `{}` to include expressions.
+
+```js
+let name = "Alice";
+let greeting = f"Hello, {name}!";
+print(greeting); // Hello, Alice!
+
+let x = 10;
+let y = 5;
+print(f"{x} + {y} = {x + y}"); // 10 + 5 = 15
+print(f"{x} - {y} = {x - y}"); // 10 - 5 = 5
+print(f"{x} * {y} = {x * y}"); // 10 * 5 = 50
+print(f"{x} / {y} = {x / y}"); // 10 / 5 = 2
+```
+
+F-strings can contain any valid AIScript expression inside the curly braces. The expressions are evaluated at runtime and their results are converted to strings. This makes f-strings particularly useful for:
+
+- String interpolation with variables
+- Embedding arithmetic expressions
+- Calling functions within strings
+- Formatting complex data structures
+
 ## Control flow
 
 ```js
@@ -270,7 +294,6 @@ let d = a[:2]; // "AI"
 
 ```
 
-
 ## Loops
 
 AIScript only has two keyword for loops: `for` and `while`.
@@ -320,7 +343,7 @@ let person = {
 };
 
 for (key, value) in person {
-    print("{key}: {value}");
+    print(f"{key}: {value}");
 }
 ```
 
@@ -332,7 +355,6 @@ for i in 1..10 {
 }
 ```
 
-
 ### Break and Continue
 
 ```js
@@ -359,4 +381,4 @@ AIScript provide a convenient way to access environment variables, the syntax is
 ```rust
 let home = $HOME;
 print(home);
-```
+```

docs/guide/language/closure-lambda.md

@@ -104,26 +104,6 @@ print(math.multiply(5)); // 10
 print(math.combined(5)); // 30
 ``` -->
 
-<!-- ## Partial Application
-
-Use closures to create partially applied functions:
-
-```js
-fn partial(func, ...fixed_args) -> fn {
-    return |...args| func(...fixed_args, ...args);
-}
-
-fn greet(greeting, name) -> str {
-    return "{greeting}, {name}!";
-}
-
-let hello = partial(greet, "Hello");
-let goodbye = partial(greet, "Goodbye");
-
-print(hello("Alice"));  // "Hello, Alice!"
-print(goodbye("Bob"));  // "Goodbye, Bob!"
-``` -->
-
 ## Immediate Invocation
 
 You can immediately invoke a lambda after defining it:
@@ -166,9 +146,9 @@ Closures are ideal for event-driven or asynchronous programming:
 fn fetch_data(url: str, on_success, on_error) {
     // Simulating an async operation
     if url.starts_with("https") {
-        on_success("Data from {url}");
+        on_success(f"Data from {url}");
     } else {
-        on_error("Invalid URL: {url}");
+        on_error(f"Invalid URL: {url}");
     }
 }
 

docs/guide/language/enum-match.md

@@ -196,9 +196,9 @@ let point = [10, 20];
 
 match point {
     [0, 0] => print("At origin"),
-    [0, y] => print("On y-axis at y={y}"),
-    [x, 0] => print("On x-axis at x={x}"),
-    [x, y] => print("At position ({x}, {y})"),
+    [0, y] => print(f"On y-axis at y={y}"),
+    [x, 0] => print(f"On x-axis at x={x}"),
+    [x, y] => print(f"At position ({x}, {y})"),
 };
 ```
 
@@ -213,7 +213,7 @@ match num {
     n if n % 15 == 0 => print("FizzBuzz"),
     n if n % 3 == 0 => print("Fizz"),
     n if n % 5 == 0 => print("Buzz"),
-    n => print("{n}"),
+    n => print(f"{n}"),
 };
 ```
 

docs/guide/web/database.md

@@ -73,12 +73,12 @@ let tx = pg.begin_transaction();
 
 // Execute multiple operations within the transaction
 tx.query("INSERT INTO users (name, email) VALUES($1, $2);", "Alice", "[email protected]") |err| {
-    print("Transaction failed: {err}");
+    print(f"Transaction failed: {err}");
     tx.rollback();
     return;
 };
 tx.query("INSERT INTO user_roles (user_id, role) VALUES(LASTVAL(), 'admin');") |err| {
-    print("Transaction failed: {err}");
+    print(f"Transaction failed: {err}");
     tx.rollback();
     return;
 };
@@ -132,12 +132,12 @@ use std.db.sqlite;
 let tx = sqlite.begin_transaction();
 
 tx.query("INSERT INTO notes (title, content) VALUES($1, $2);", "Note 1", "Content 1") |err| {
-    print("Transaction failed: {err}");
+    print(f"Transaction failed: {err}");
     tx.rollback();
     return;
 };
 tx.query("INSERT INTO notes (title, content) VALUES($1, $2);", "Note 2", "Content 2") |err| {
-    print("Transaction failed: {err}");
+    print(f"Transaction failed: {err}");
     tx.rollback();
     return;
 };

docs/guide/web/openapi-docs.md

@@ -19,7 +19,7 @@ post /api/chat {
         message: str,
     }
 
-    return "Input: " + body.message + "!";
+    return f"Input: {body.message}!";
 }
 ```
 

docs/guide/web/route.md

@@ -54,7 +54,7 @@ get /hello {
         name: str = "Alice"
     }
 
-    return "Hello, " + query.name + "!";
+    return f"Hello, {query.name}!";
 }
 ```
 
@@ -93,7 +93,7 @@ post /hello {
         name: str
     }
 
-    return "Hello, " + body.name + "!";
+    return f"Hello, {body.name}!";
 }
 ```
 
@@ -113,7 +113,7 @@ post /hello {
         name: str
     }
 
-    return "Hello, " + body.name + "!";
+    return f"Hello, {body.name}!";
 }
 ```
 
@@ -136,7 +136,7 @@ get /hello {
     header.test = "Test Header";
     // Modify cookie
     cookie.xyz = "changed";
-    return "header: abc={abc}, cookie: xyz={xyz}";
+    return f"header: abc={abc}, cookie: xyz={xyz}";
 }
 ```
 
@@ -150,7 +150,7 @@ get /hello {
     let scheme = request.scheme;
     let host = request.host;
     let port = request.port;
-    return "method: {method}, url: {url}, path: {path}, scheme: {scheme}, host: {host}, port: {port}";
+    return f"method: {method}, url: {url}, path: {path}, scheme: {scheme}, host: {host}, port: {port}";
 }
 ```
 

docs/reference/route/keyword.md

@@ -128,7 +128,7 @@ get /search {
 
     let term = query.term;
     let page = query.page;
-    return "Searching for '{term}' on page {page}";
+    return f"Searching for '{term}' on page {page}";
 }
 ```
 
@@ -145,7 +145,7 @@ get /users/:id/posts/:postId {
 
     let userId = path.id;
     let postId = path.postId;
-    return "Accessing post {postId} for user {userId}";
+    return f"Accessing post {postId} for user {userId}";
 }
 ```
 
@@ -175,7 +175,7 @@ Access request headers through the `header` object.
 get /headers {
     let userAgent = header["User-Agent"];
     let contentType = header["Content-Type"];
-    return "User-Agent: {userAgent}, Content-Type: {contentType}";
+    return f"User-Agent: {userAgent}, Content-Type: {contentType}";
 }
 ```