lang/zig/while.zig


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const expect = @import("std").testing.expect;

test "while basic" {
    var i: usize = 0;
    while (i < 10)
        i += 1;
    expect(i == 10);
}

test "while break" {
    var i: usize = 0;
    while (true) {
        if (i == 10)
            break;
        i += 1;
    }
    expect(i == 10);
}

test "while continue" {
    var i: usize = 0;
    while (true) {
        i += 1;
        if (i < 10)
            continue;
        break;
    }
    expect(i == 10);
}

test "while loop continue expression" {
    var i: usize = 0;
    while (i < 10) : (i += 1) {}
    expect(i == 10);
}

test "while loop continue expression, more complicated" {
    var i: usize = 1;
    var j: usize = 1;
    while (i * j < 2000) : ({ i *= 2; j *= 3; })
        expect(i * j < 2000);
}

test "while else" {
    expect(rangeHasNumber(0, 10, 5));
    expect(!rangeHasNumber(0, 10, 15));
}

fn rangeHasNumber(begin: usize, end: usize, number: usize) bool {
    var i = begin;
    return while (i < end) : (i += 1) {
        if (i == number) {
            break true;
        }
    } else false;
}

test "nested break" {
    outer: while (true) {
        while (true) {
            break :outer;
        }
    }
}

test "nested continue" {
    var i: usize = 0;
    outer: while (i < 10) : (i += 1) {
        while (true) {
            continue :outer;
        }
    }
}