haskell-ShellCheck - shell script analysis tool

The goals of ShellCheck are:

* To point out and clarify typical beginner's syntax issues, that causes a shell
  to give cryptic error messages.
* To point out and clarify typical intermediate level semantic problems, that
  causes a shell to behave strangely and counter-intuitively.
* To point out subtle caveats, corner cases and pitfalls, that may cause an
  advanced user's otherwise working script to fail under future circumstances.
