Warning: This answer is contested. See comments.
def doAppend( size=10000 ): result = [] for i in range(size): message= "some unique object %d" % ( i, ) result.append(message) return result def doAllocate( size=10000 ): result=size*[None] for i in range(size): message= "some unique object %d" % ( i, ) result[i]= message return result
Results. (evaluate each function 144 times and average the duration)
simple append 0.0102 pre-allocate 0.0098
Conclusion. It barely matters.
Premature optimization is the root of all evil.
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