I want to use IRB as a shell for my GNU/Linux system (portablility is desired but not a requirement at this point). How I hope to acheive this is to loop through each directory in the $PATH variable, then through each file in those directories and dynamically create a function named as the files name (automatically create a function for ‘/usr/bin/konsole’ named ‘konsole()’). I’m doing much more but this is kind of the corner stone of the whole project and I just can’t figure out how to create functions with the contents of a variable as it’s name. Is this even possible? If it is could someone give me a simple example of just the function creation?
You can do that using the metaprogramming eval method. For example:
x = 'test'
eval("def #{x}; puts 'Hello world'; end")
test
The eval method takes a string and parses it into code; you can insert variable values into it as I have done here. The idea that doing this is evil is a bit overblown. It’s not a good idea to do it unless you have a clear idea of what you are up to, though. In this particular use case it’s the way to do the job.