LYR-PAR0062

a 'comptime for' in an initializer without '[f] = e'

error · spec 11-metaprogramming

In an initializer, a comptime for (f in …) is followed by something else than an item [f] = e.

Explanation

A comptime for in an initializer sets one field per round, the field its variable names: Point { comptime for (f in fields<Point>()) [f] = 0 }. A field written by its own name would be set once per round.

Write the item as [f] = value.

Wrong

import std.meta { fields };

struct Point { x: int, y: int }

fn main(): void {
    let p = Point { comptime for (f in fields<Point>()) x = 0 };
    let _ = p.x;
}

Right

import std.meta { fields };

struct Point { x: int, y: int }

fn main(): void {
    let p = Point { comptime for (f in fields<Point>()) [f] = 0 };
    let _ = p.x;
}