laughinghan/mathquill — comment on commit d4ded2cd815d57d1d9c6272690c1366b6bc135b8
File:  line 0
By jayferd:

map takes an enumerable to an array - that's how it works in Ruby, Haskell, and Python, anyways. Throwing `'break'` allows you to break out of map, fold, and other iterator methods where returning `false` doesn't necessarily mean "stop". And I believe the error object should still have the same stack trace even if it's caught and re-thrown, so you can still debug things.