Chapter 25: What's New in v1.11

v1.11 is "The Developer Experience Release" - focused on making developers productive in their first hour.

New Language Features

enum.to_string()

Enums now have a .to_string() method that returns the variant name as a string:

enum Color { Red, Green, Blue }

println(Color.Red.to_string())   // "Red"

var c = Color.Blue
println(c.to_string())           // "Blue"

Previously, .to_string() on an enum returned the integer value ("0", "1", etc.), which was confusing and useless for debugging.

Indexed Iteration

You can now get both the index and value when iterating over an array:

var fruits = ["apple", "banana", "cherry"]
for i, v in fruits {
    println(i.to_string() + ": " + v)
}
// 0: apple
// 1: banana
// 2: cherry

This is similar to Python's enumerate() or Go's for i, v := range.

String Repeat Operator

Multiply a string by an integer to repeat it:

println("ha" * 3)    // "hahaha"
println("-" * 40)     // 40 dashes

Optional Type Syntax

int? is shorthand for OptionInt:

var x: int? = OptionInt_Some(42)
var y: int? = OptionInt_None()
println(OptionInt_unwrap(x).to_string())       // 42
println(OptionInt_unwrap_or(y, 0).to_string())  // 0

Compiler Improvements

Missing Return is an Error

Functions with a return type that don't return on all paths now fail to compile:

fn get() -> int {
    // v1.10: Warning (compiles, returns garbage)
    // v1.11: Error - won't compile
}

This catches a whole class of silent bugs.

Type Mismatch Errors

Type errors now come from Wyn with clear messages:

Error: Type mismatch at line 2
  Expected: int (integer)
  Got:      string (text string)
  Suggestion: use .to_int() to parse the string

Typed Arrays

var arr: [int] = [] uses a specialized representation with raw long long* storage - no type tags, no boxing. Building and summing a 1M-element int array takes ~11ms.

Tooling

• wyn build now shows binary size and compile time: ✓ Built: myapp (51KB, 295ms)
• wyn test works from any project directory (no longer requires being in the compiler directory)
• wyn fmt --check exits non-zero if files need formatting (for CI)
• wyn init now creates a .gitignore file
• Missing packages show: Error: Package 'redis' not installed → Run: wyn pkg install redis
• Unknown commands show: Error: Unknown command 'bild' → Did you mean wyn build?

Upgrading

No breaking changes except:

1. Functions with missing returns that compiled with a warning will now fail. Add the missing return.
2. enum.to_string() returns the variant name instead of the integer. If you need the integer, use int_to_string().