I haven't seen an answer to this specific question anywhere. My apologies if someone identifies it as a dupe. What I am wondering is: is it possible to search for:
abcdefghijk
matching any of the following:
a bcdefghijk
ab cdefghijk
abc defghijk
abcd efghijk
abcde fghijk
abcdef ghijk
abcdefg hijk
abcdefgh ijk
abcdefghi jk
abcdefghij k
I.e. I know the string I want to find, but it can end up with a stray space at any place.
Seems like this may be out of scope with regex, but wanted to be sure.
CodePudding user response：
One approach would be to use a positive lookahead to find a space combined with a negative lookahead to not find a space.
Then let every character be followed by an optional space.
^(?=.* (?!.* ))?a ?b ?c ?d ?e ?f ?g ?h ?i ?j ?k ?$
(?=- positive lookahead start.*- anything followed by space(?!- negative lookahead start.*- anything followed by a space
)- negative lookahead end
)- positive lookahead end?- 0 or 1 match