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Simple question, say I have two regular expressions
rtmp.*?\b/
rtmp.+?\b/
It seems to be negligible difference if any on the tests I have done.
I understand the technical difference between the two expressions. In my case either will do. As the question states I am simply asking about the performance difference, if any. One difference I noticed is that + requires egrep
grep 'rtmp.*?\b/'
egrep 'rtmp.+?\b/'
These two expressions:
match different things.
*means “zero or more of the previous expression” (i.e. any number),+means “one or more of the previous expression”. So.*?matches any number of any characters in non-greedy mode and.+?matches any positive number of any characters in non-greedy mode.The speed difference is immaterial, use the expression that matches your intent.