Problem Statement

List the conditional structures offered by a programming language. See Wikipedia: conditionals for descriptions. Common conditional structures include if-then-else and switch. Less common are arithmetic if, ternary operator and Hash-based conditionals. Arithmetic if allows tight control over computed gotos, which optimizers have a hard time to figure out.

Let's start with the solution:

#lang transd

MainModule: {
    _start: (λ locals: b 1 c 0
        (textout (if b "OK" else "NO") "\n")

        // switch/case emulation

        (textout (* 5
            (if (== b 0) 2
            elsif (== b 1) 5
            else 6)) "\n")

        // example of using 'or' as a conditional construct

        (or (!= c 0) (textout "c is 0"))
    )
}