Imagine you are trying to pattern match "stackoverflow".
You want the following:
this is stackoverflow and it rocks [MATCH]
stackoverflow is the best [MATCH]
i love stackoverflow [MATCH]
typostackoverflow rules [NO MATCH]
i love stackoverflowtypo [NO MATCH]
I know how to parse out stackoverflow if it has spaces on both sites using:
/\s(stackoverflow)\s/
Same with if its at the start or end of a string:
/^(stackoverflow)\s/
/\s(stackoverflow)$/
But how do you specify "space or end of string" and "space or start of string" using a regular expression?
ベストアンサー1
You can use any of the following:
\b #A word break and will work for both spaces and end of lines.
(^|\s) #the | means or. () is a capturing group.
/\b(stackoverflow)\b/
Also, if you don't want to include the space in your match, you can use lookbehind/aheads.
(?<=\s|^) #to look behind the match
(stackoverflow) #the string you want. () optional
(?=\s|$) #to look ahead.