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wlab

WLAB (WLAng Bootstrap) is an LLVM-based compiler written from scratch (Github).

Features

• Helpful error messages
• Name Mangling
• DWARF debug info
• Visibility
• Function and struct attributes
• Multi-file support
• If statements
• Type inference
• Structs

Example program

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#![declare_crate(hello_world)]
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struct Messages {
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    first: str,
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    second: str,
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    override: bool,
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};
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fn get_messages() -> Messages {
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    /*
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     * The last statement in a code block will be implicitly returned if it is 
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     * not terminated by a semicolon
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     */
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    Messages {
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        override: true,
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        first: "This will be printed first",
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        second: "This will be not printed",
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    }
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}
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fn main() {
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    // Variable types are automatically inferred //
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    let mut messages = get_messages();
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    // `if` statements do not require parenthesis //
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    if messages.override {
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        messages.second = "This will be printed second";
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    }
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    std::println(messages.first);
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    std::println(messages.second);
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    // `if` can be used as an expression //
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    let third_message = if 2 + 2 == 4 {
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        "This will be printed third"
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    } else {
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        "This will not be printed"
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    };
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    std::println(third_message);
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}

Error messages

src:

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#![declare_crate(a)]
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fn foo(x: bool) {
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    if x {
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        loop {std::println("this will loop forever")};
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    } else {
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        std::exit(1);
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    }
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    std::println("This will never be printed")
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}

error:

src:

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#![declare_crate(a)]
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struct Foo {
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    x: i32,
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    y: i32,
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};
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fn main() {
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    let foo = Foo { x: 6, y: 12 }; // by default all variables are immutable
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    foo.y = 10;
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}

error: