CSCI E-168

A couple of weeks ago I mentioned the “cheat” gem which has a plethora of useful quick docs on various topics such as regular expressions. I breezed through the install — and fix for Ruby 1.9.1 — here it is, for the record:

gem install cheat
# NOTE: If you're on Linux or OS/X and have a standard install (rather than using the ruby_switch.sh script, you want to do sudo gem install cheat)

If you run it under 1.9.x, you should get an error like so:

cheat regexp
/Users/jnorman/.gem/ruby/1.9.1/gems/cheat-1.2.1/lib/cheat.rb:150:in `cache_dir': uninitialized constant Cheat::PLATFORM (NameError)
	from /Users/jnorman/.gem/ruby/1.9.1/gems/cheat-1.2.1/lib/cheat.rb:16:in `sheets'
	from /Users/jnorman/.gem/ruby/1.9.1/gems/cheat-1.2.1/bin/cheat:4:in `<top (required)>'
	from /Users/jnorman/.gem/ruby/1.9.1/bin/cheat:19:in `load'
	from /Users/jnorman/.gem/ruby/1.9.1/bin/cheat:19:in `<main>'

What you want to do is edit the file producing the error (in my case, from the exception trace, /Users/jnorman/.gem/ruby/1.9.1/gems/cheat-1.2.1/lib/cheat.rb). Go to the line, and change the constant PLATFORM to RUBY_PLATFORM. Save the file.

And voila!

chelsea:~ jnorman$ cheat regexp
regexp:
  A regexp's form is written /pattern/modifiers where "pattern" is the regular
# much deleted

For help,

cheat cheat