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//
// Believe it or not, sometimes things go wrong in programs.
//
// In Zig, an error is a value. Errors are named so we can identify
// things that can go wrong. Errors are created in "error sets", which
// are just a collection of named errors.
//
// We have the start of an error set, but we're missing the condition
// "TooSmall". Please add it where needed!
const MyNumberError = error{
TooBig,
???,
TooFour,
};
const std = @import("std");
pub fn main() void {
var nums = [_]u8{ 2, 3, 4, 5, 6 };
for (nums) |n| {
std.debug.print("{}", .{n});
const number_error = numberFail(n);
if (number_error == MyNumberError.TooBig) {
std.debug.print(">4. ", .{});
}
if (???) {
std.debug.print("<4. ", .{});
}
if (number_error == MyNumberError.TooFour) {
std.debug.print("=4. ", .{});
}
}
std.debug.print("\n", .{});
}
// Notice how this function can return any member of the MyNumberError
// error set.
fn numberFail(n: u8) MyNumberError {
if (n > 4) return MyNumberError.TooBig;
if (n < 4) return MyNumberError.TooSmall; // <---- this one is free!
return MyNumberError.TooFour;
}
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