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@davisagli
Created April 6, 2012 07:42
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Marmoset patching
import inspect
def marmoset_patch(func, s, r):
source = inspect.getsource(func).replace(s, r)
exec source in func.func_globals
func.func_code = func.func_globals[func.__name__].func_code
def foo():
print 1
print 2
print 3
foo()
# 1
# 2
# 3
marmoset_patch(foo, '3', "'ZOMG'")
foo()
# 1
# 2
# ZOMG
@davisagli
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Please, don't actually do this.

@matthewryanscott
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Too late... you let the marmoset out of the bag!

@khs
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khs commented Apr 7, 2012

This seems like a good idea. Thank you for helping a new programmer out with learning new techniques. :) More seriously, what is monkey patching?

@codlark
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codlark commented Apr 7, 2012

@kellerkeller
a monkey patch is when you re-open an object for modification, some languages like ruby allow for this, and it's very common for large ruby apps to build classes out of several files. Python discourages monkey patching as looking through multiple files for where a method is defined gets tired fast, like the first time it happens, and as the Zen of Python tells us, explicit is better than implicit

@ctheune
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ctheune commented Mar 19, 2013

O M G

@sureshvv
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Have the python people heard of this?

@miohtama
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This technique intrigues me. I look forward to apply it in many real-life scenarios.

@ztane
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ztane commented Feb 17, 2014

This is so wrong, the right solution is to use AST rewriting!

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