The _check used for creation of words makes it slower #8287
Description
The _check function of the Combinatorial class of all words (checking that the 40 first letters of the word are in the parent) is called for each word created by the user ....and by any other function. It would be good to add a check parameter (True or False) whether to do the checking. For example, for internal function, it could be turned off. Here is a example of what can be gained from this modification when generating all words of a given length :
BEFORE:
sage: W = Words([0,1])
sage: time l = list(W.iterate_by_length(15))
CPU times: user 2.60 s, sys: 0.09 s, total: 2.69 s
Wall time: 2.71 s
AFTER:
sage: W = Words([0,1])
sage: time l = list(W.iterate_by_length(15))
CPU times: user 1.99 s, sys: 0.06 s, total: 2.05 s
Wall time: 2.08 s
CC: @videlec
Component: combinatorics
Reviewer: Vincent Delecroix
Issue created by migration from https://trac.sagemath.org/ticket/8287