Conditional compilation

// Support for multiple conditions in one branch
$if ios || android {
    println('Running on a mobile device!')
}
$if linux && x64 {
    println('64-bit Linux.')
}
// Usage as expression
os := $if windows { 'Windows' } $else { 'UNIX' }
println('Using $os')
// $else-$if branches
$if tinyc {
    println('tinyc')
} $else $if clang {
    println('clang')
} $else $if gcc {
    println('gcc')
} $else {
    println('different compiler')
}
$if test {
    println('testing')
}
// v -cg ...
$if debug {
    println('debugging')
}
// v -d option ...
$if option ? {
    println('custom option')
}

If you want an if to be evaluated at compile time it must be prefixed with a $ sign. Right now it can be used to detect an OS, compiler, platform or compilation options. $if debug is a special option like $if windows or $if x32. If you’re using a custom ifdef, then you do need $if option ? {} and compile withv -d option. Full list of builtin options: