use std const main = {	check("aaab", "aaa", "b")	check("aaa", "aaa", "")	check("aa", "aaa", "aa")} const check = {sl, pfx, expected	var r 	r = sl	std.chomp(&r, pfx)	std.assert(std.eq(r, expected), \		"expected chomp({}, {}) => {}, got {}\n", sl, pfx, expected, r)}