Let’s say you want to know what symbols are added when you require something in ruby. For example, I was curious if I could get a list of symbols that were added when I required ‘english’.

I simply used Symbol.all_symbols to save off the old symbol array and the new one and then subtracted the two arrays.

before = Symbol.all_symbols
require 'english'
after = Symbol.all_symbols
added_symbols = after - before 
p added_symbols # should be an Array of symbols added.
puts added_symbols.count # I get 35.

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