Crystal Run : shebang wrapper for Crystal

crun is a tool enabling one to put a "bang line" in the source code of a Crystal program to run it, or to run such a source code file explicitly. It was inspired by gorun and created in an attempt to make experimenting with Crystal more appealing to people used to Ruby and similar languages which operate most visibly with source code.

#!/usr/bin/env crun

puts "Hello world"

then simply run:

$ chmod +x
$ ./
Hello world!

Also Crun is able to handle comments pointing to shards dependencies of a classical shards.yml file:

#!/usr/bin/env crun
# ---
# minitest:
#   github: ysbaddaden/
# ...

require "minitest/autorun"

# ....