feat(docs): update docs (#583)

feat(docs): update docs

Updates the Wing docs. See details in [workflow run].

[Workflow Run]: https://github.com/winglang/docsite/actions/runs/6018610819

------

*Automatically created via the "update-docs" workflow*

versioned_docs/version-latest/03-language-reference.md

@@ -516,12 +516,10 @@ log("UTC: ${t1.utc.toIso())}");            // output: 2023-02-09T06:21:03.000Z
 | Name     | Extra information                                        |
 | -------- | -------------------------------------------------------- |
 | `log`    | logs str                                                 |
-| `throw`  | creates and throws an instance of an exception           |
 | `assert` | checks a condition and _throws_ if evaluated to false    |
 
 > ```TS
 > log("Hello ${name}");
-> throw("a recoverable error occurred");
 > assert(x > 0);
 > ```
 
@@ -1173,7 +1171,7 @@ The loop invariant in for loops is implicitly re-assignable (`var`).
 
 ### 2.7 while
 
-**while** statement is used to execute a block of code while a condition is true.  
+The **while** statement evaluates a condition, and if it is true, a set of statements is repeated until the condition is false.
 
 > ```TS
 > // Wing program:
@@ -1186,6 +1184,20 @@ The loop invariant in for loops is implicitly re-assignable (`var`).
 
 ---
 
+### 2.8 throw
+
+The **throw** statement raises a user-defined exception, which must be a string expression.
+Execution of the current function will stop (the statements after throw won't be executed), and control will be passed to the first catch block in the call stack.
+If no catch block exists among caller functions, the program will terminate.
+(An uncaught exception in preflight causes a compilation error, while an uncaught exception in inflight causes a runtime error.)
+
+> ```TS
+> // Wing program:
+> throw "Username must be at least 3 characters long.";
+> ```
+
+[`▲ top`][top]
+
 ## 3. Declarations
 
 ### 3.1 Structs