regex only include a match if it's exact

Question

I've got some code that reads files line by line. It needs to match each line for tags that have the following names:

My code builds a tree of tags from the data on a page, and then maps through the tree to compare the node names with the list above. I need to match the name with one of those exactly, or exclude it entirely.

The issue I'm having is that when one of the tag names has a portion of any of the names in the list, that name is added. For example:

respdate
date

the code includes the tag for 'respdate' as well as 'date'. How do I make the regex exclude respdate entirely since it doesn't match "date" exactly?

score 1 · Accepted Answer · answered Feb 15 '16 at 19:28

1

One option is to use the word boundaries metacharacter, \b.

Group all of your words in a non-capturing group and surround the group with word boundaries on both sides:

\b(?:root|date|year)\b

answered Feb 15 '16 at 19:28

Josh Crozier

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fastest most awesome answer I've ever gotten on SO. You da man, Josh. Thanks. – Nick Res Feb 15 '16 at 19:31
1

And one of the most duplicate ones. – Wiktor Stribiżew Feb 15 '16 at 19:33

regex only include a match if it's exact

1 Answers1