What's the idiomatic syntax for prepending to a short python list?

python list prepend
hurrymaplelad picture hurrymaplelad · Dec 16, 2011 · Viewed 310.5k times · Source

list.append() is the obvious choice for adding to the end of a list. Here's a reasonable explanation for the missing list.prepend(). Assuming my list is short and performance concerns are negligible, is 

list.insert(0, x)

or 

list[0:0] = [x]

idiomatic?

Answer

Raymond Hettinger picture Raymond Hettinger · Dec 16, 2011

The s.insert(0, x) form is the most common.

Whenever you see it though, it may be time to consider using a collections.deque instead of a list.

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