sample.gr

/*
   Sample file that our gorepl can interpret
   This is a block commen
   See also the other *.gr files
*/
unless = macro(cond, iffalse, iftrue) {
    quote(if (!(unquote(cond))) {
        unquote(iffalse)
    } else {
        unquote(iftrue)
    })
}

unless(10 > 5, print("BUG: not greater\n"), print("macro test: greater\n"))

// first class function objects, can also be written as `func fact(n) {` as shorthand
// or fact = (n => ...) as a lambda short form.
fact=func(n) {
    log("called fact ", n) // log (timestamped stderr output)
    if (n<=1) {
        return 1
    }
    /* recursion: */ n*self(n-1) // also last evaluated expression is returned (ie return at the end is optional)
}

a=[fact(5), "abc", 76-3, sqrt(2)] // array can contain different types, grol also has math functions.

m={"key": a, 73: 29} // so do maps

println("m is:", m) // stdout print
println("Outputting a smiley: 😀")

first(m.key) // get the value from key from map, which is an array, and the first element of the array is our factorial 5
// (dot notation .key is shorthand for ["key"]), could also have been first(m["key"]) or m["key"][0] or m.key[0]

// ^^^ gorepl sample.gr should output 120