Bug: Option 'else' block syntax fails to parse

[mjm918]

Description

The documented else block syntax for handling none values in options fails to parse.

Documented Syntax (from language-reference.md)

var value: int = get_optional() else {
    // Handle none case
    return -1;
};

Error

When using this syntax, the parser reports multiple errors including:

• ExpectedExpr
• Expected(Semicolon)

Reproduction

fn main() {
    var opt: option<int> = none;
    var value: int = opt else {
        0
    };
    println(value);
}

Expected Behavior

The else block should parse correctly and execute the block when the option is none, using the block's final expression as the value.

Workarounds

Use ?? operator instead:

var value: int = opt ?? 0;

Notes

The ?? operator and ! force unwrap work correctly. Only the else block syntax is affected.

[mjm918]

Closing this issue - the syntax was misunderstood.

The else block is for side effects (logging, early return), not for providing a default value. The correct syntax is:

var value: int = opt else { 
    println("logging when none"); 
} ?? 0;

• else { ... } - executes when option is none (for side effects)
• ?? default - provides the actual default value

This is different from Rust/Swift where the else block provides the value.