Regular Expressions 101

classthe literal text class (case sensitive)

Positive Lookahead(?=="(?:field|.*?\sfield|field\s.*?|.*?\sfield\s.*?)")

="the literal text ="

Non-Capturing Group(?:field|.*?\sfield|field\s.*?|.*?\sfield\s.*?)

1st Alternativefield

fieldthe literal text field (case sensitive)

2nd Alternative.*?\sfield

.*?any character (except for line terminators), repeated any number of times

\sany whitespace character

fieldthe literal text field (case sensitive)

3rd Alternativefield\s.*?

fieldthe literal text field (case sensitive)

\sany whitespace character

.*?any character (except for line terminators), repeated any number of times

4th Alternative.*?\sfield\s.*?

.*?any character (except for line terminators), repeated any number of times

\sany whitespace character

fieldthe literal text field (case sensitive)

\sany whitespace character

.*?any character (except for line terminators), repeated any number of times

"the literal " (34₁₀ / 42₈ / 22₁₆)

Global pattern flags

g modifier: global. Finds all matches instead of stopping after the first

Detailed match information will be displayed here automatically.

Search reference

Regular Expression

class(?=="(?:field|.*?\sfield|field\s.*?|.*?\sfield\s.*?)")

New

Ex1: should match both of these:

<div class="something else field">Foo</div>
<div class="field something else">Foo</div>
<span class="field">Bar</span>
<span class="foo field bar">Bar</span>
Ex2: should not match

<div class="baseball-field baz">Baz</div>