An implicit
require "prelude"gets inserted into the beginning of all crystal programs, and will either load this file, or a different crystal file if the--prelude <new-prelude>build option is provided.
I don’t quite understand what you’re saying, but, i use this hack too add some crack code before run an crystal application. e.g. like following:
crystal run --prelude hacked_prelude "$@"
Assume following is the content of hacked_prelude.cr
require "prelude"
# others code need to run before run app
This feature almost same as the usage of $RUBYOPT ENV for Ruby.