I want to bind a local variable with lambda

Not what I expected ...

>>> funcs = []
>>> for fruit in [ 'apple', 'orange', 'banana' ]:
...     funcs.append(lambda: 'I like ' + fruit)
... 
>>> for f in funcs:
...     print f()
... 
I like banana
I like banana
I like banana

Python's lambda resolves the name of the variable at the time of the call, so it becomes "fruit" (='banana') at the time of execution.

Solution

Change lambda:'I like' + fruit to lambda fruit = fruit:'I like' + fruit.

I think that it is standard to solve functionally with higher-order functions, but if it is ↑, it is good to go with one-liner. (^ ◇ ^)

>>> funcs = []
>>> for fruit in [ 'apple', 'orange', 'banana' ]:
...     funcs.append(lambda fruit=fruit: 'I like ' + fruit)
... 
>>> for f in funcs:
...     print f()
... 
I like apple
I like orange
I like banana

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