ziglings/exercises/23_errors3.zig
2021-02-15 16:55:44 -05:00

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620 B
Zig

//
// One way to deal with error unions is to "catch" any error and
// replace it with a default value.
//
// foo = canFail() catch 6;
//
// If canFail() fails, foo will equal 6.
//
const std = @import("std");
const MyNumberError = error{TooSmall};
pub fn main() void {
var a: u32 = addTwenty(44) catch 22;
var b: u32 = addTwenty(4) ??? 22;
std.debug.print("a={}, b={}", .{ a, b });
}
// Please provide the return type from this function.
// Hint: it'll be an error union.
fn addTwenty(n: u32) ??? {
if (n < 5) {
return MyNumberError.TooSmall;
} else {
return n + 20;
}
}