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Thank you! I've been trying to wrap my head around decorators this past week. Definitely a good guide.

• kaens 18y ago
  Really, the only thing you need to wrap your head around to understand decorators is the concept of first-class functions (functions that can take functions as parameters and return functions). If you understand those, and how they can be useful, the only remaining step to python's decorators is a syntactic transformation. def decorate(func): def wrapper(*args, **kwargs): print "I'm decorated!" return func(*args, **kwargs) return wrapper @decorate def foo(): print "I'm foo!" Above, @decorate is equivalent to having foo = decorate(foo) underneath the definition of foo. Decorate takes a function X as a parameter, creates a function Y that takes whatever arguments, prints a statement, and returns the value of calling Y with whatever arguments. It then returns the object representing X. If you need a bunch of good examples of how first-class functions can be extremely useful, go through a bit of SICP ( http://mitpress.mit.edu/sicp/full-text/book/book.html http://mitpress.mit.edu/sicp/full-text/book/book.html ). It's a challenging tome, but well worth the effort.