Today I Learned

hashrocket A Hashrocket project

Run Code if Current File is Calling File

This conditional tells Ruby to execute the code within if the current file is the file running the code.

# exec.rb
if __FILE__ == $0
  puts 'shown when exec.rb is run directly; not when required'

This works by comparing the current file (__FILE__) with the file that started the program ($0). If they aren't the same (exec.rb), the statement will not be printed.

See More #ruby TILs
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