If ... else

ABS supports basic if statements:

if x > 0 {
    echo("hello world")
}

as well as else and else if alternatives:

if x > 0 {
    echo("x is high")
} else if x < 0 {
    echo("x is low")
} else {
    echo("x is actually zero!")
}

You can wrap conditions in parentheses, although we believe that, from a readability standpoint, it's usually better to omit them:

if (x > 0) {
    echo("hello world")
}