Looking for a character OR a sequence in regex

Question

I'm trying to write a regex that detects multiple patterns in a text, among which a sequence of more than one space. I'm doing stuff like this:

/[abc( {2,})]/

But it seems to also detect the single space. What am I doing wrong?

Answer 1

The [abc( {2,})] pattern is a character class (or bracket expression in other terminology) that matches a single char, a, b, c, (, space, {, 2, ,, } or ). You cannot define char sequences inside character classes.

You may use

[abc]| {2,}

Or, to match any 2 or more whitespaces, use

[abc]|\s{2,}

The | alternation operator is used to separate two alternatives here:

• [abc] - a character class (bracket expression) that matches a single char, either a, b or c
• | - or
• {2,} - two or more spaces.

NOTE: Whenever you want to use this alternation inside a longer pattern it is a good idea to wrap it with a group so that it does not "corrupt" the overall regex:

([abc]| {2,})

Or, with a non-capturing group if you needn't access to the value captured with these patterns:

(?:[abc]| {2,})