I am not very good with regular expression.

I have a string like:

var bigString = 'abc,xyz,def';

I want to create a regular expression that it looks for either preceding mas or ma at the end.

e.g:

Valid expressions will be : abc, ,xyz, ,def

I will appreciate any kind of help.

I am not very good with regular expression.

I have a string like:

var bigString = 'abc,xyz,def';

I want to create a regular expression that it looks for either preceding mas or ma at the end.

e.g:

Valid expressions will be : abc, ,xyz, ,def

I will appreciate any kind of help.

• javascript
• regex

• 1 Are those the only valid values? Is "abc" valid? – Ateş Göral Commented Apr 26, 2012 at 15:36
• Just alphabetical characters, or alpha-numerics? – David Thomas Commented Apr 26, 2012 at 15:37
• Another question is, WHY? Maybe the problem you're trying to solve doesn't require a regular expression. Can you tell what you're exactly trying to do? – Ateş Göral Commented Apr 26, 2012 at 15:41
• 1 "Valid expressions will be : abc, ,xyz, ,def" - /(abc,)|(,xyz,)|(,def)/ QED. – Neil Commented Apr 26, 2012 at 15:44

4 Answers 4

Well that regex would be:

/(?:,[A-Za-z]+)|(?:[A-Za-z],)/

/(,\w+)|(\w+,)/

This one will explicitly match where a ma is either at the beginning or the end of the string.

This should work : (UPDATED)

/(,[\w]+)|([\w]+,)/

If you are forcing a form, I would use this.
It validates strings 1,2 or 3 as one or more alpha chars with a ma before, after or both.

string1 = 'abc,'
string2 = ',xyz,'
string3 = ',def'



/^(?:[a-z]+,|,[a-z]+,?)$/i