> -z? ! -z? one bracket? two brackets? quotes? no quotes? something about a semicolon and "then", right? where can you add newlines, again? oh yeah, it's not "e

> -z? ! -z? one bracket? two brackets? quotes? no quotes? something about a semicolon and "then", right? where can you add newlines, again? oh yeah, it's not "end" like Ruby/Lua but "fi" right? what's "else if", again? really, most of these questions have only one correct answer. [ ! is never correct, neither is ! [ -z or ! [ -n. one bracket in /bin/sh, two in bash. quote every variable expansion unless you have a very good reason not to. add new lines in sensible places. nobody (sensible) complains that you can't write for num in mylist : in Python, so don't write it in shell either. the problem is there is so much cargo culting garbage. the same problem exists in "C/C++", where people write "int* buf = (int* )malloc(num*sizeof(int))" to be "compatible", or do gratuitous pointer aliasing with undefined behavior, despite the fact that any modern C implementation with any optimizations at all will inline small fixed-size memcpy.