The match op looks for a series of patterns one after the other. It doesn't look at the big picture. It can do "or" easy because it simply checks "Is A or B at this spot?". However, that's not possible with "and". "Are A and B at this spot?" is not what you want.

There are tricks to make the regex match search the string multiple times, each with a different pattern 

/^(?=.*?pat1)(?=.*?pat2)...(?=.*?patNm1)(?=.*?patN)/

[download]
/^(?=.*?pat1)(?=.*?pat2)...(?=.*?patNm1).*?patN/

[download]

but those are really just poorly readable versions of 

/pat1/ && /pat2/ && ... && /patNm1/ && /patN/

[download]

Checking if a section of the string contains matches two patterns is much harder.

In reply to Re: AND and OR on Regular Expressions by ikegami
in thread AND and OR on Regular Expressions by vitoco

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