ref: 4e018273cd06542a0605cebd840dbcb8b14ad906
dir: /lib/std/chomp.myr/
use "hasprefix" pkg std = const chomp : (str : byte[:]#, pfx : byte[:] -> bool) ;; const chomp = {str, pfx if std.hasprefix(str#, pfx) str# = str#[pfx.len:] -> true else -> false ;; }