ruby-tty-which 0.4.2-1 (armhf binary) in ubuntu groovy

 This library provides a platform-independent analogue of Unix `which`
 command.
 .
 TTY::Which has a `which` method that searches set of directories for an
 executable file based on the `PATH` environment variable, which returns
 an absolute path if the executable program exists, and `nil` otherwise.
 .
 This is part of the TTY components framework to easily build terminal
 applications in Ruby.