Result System — pass and fail

Overview

Inside regular functions (not main or failsafe), use pass and fail to return Results:

pass value — return success Result containing value
fail errcode — return error Result with the current int32 runtime error code

See guide/result/ for the canonical v0.33.6 Result handling cookbook.

Pass

func:square = int32(int32:x) {
    pass (x * x);
};

func:greet = NIL(string:name) {
    println(`Hello, &{name}!`);
    pass(NIL);           // NIL-returning functions must pass NIL
};

pass wraps the value in Result<T>{value=val, error=NIL, is_error=false}.

Fail

func:divide = flt64(int32:a, int32:b) {
    if (b == 0) {
        fail 1;          // error code 1 — division by zero
    }
    pass (a / b);
};

fail wraps the error code in Result<T>{value=<zero/NIL-shaped>, error=code, is_error=true}.

Paren Syntax

Both support optional parentheses (v0.4.6+):

pass(42);        // same as: pass 42;
fail(1);         // same as: fail 1;
pass (x * x);   // parenthesized expression (always worked)

return Keyword

return is also available and expects a full Result<T> instance:

return Result{ error: err, value: NIL, is_error: true };

In practice, pass/fail are preferred — they're more concise.