XML Shallow Parsing using Greppy API

XMLShallowParsing.php

<?php

// [^<]+
$textScanningExpression = 
    p()->not('<')->more;

// [^-]*-
$untilHyphen = 
    p()->not('-')->until->literal('-');

// $untilHyphen(?:[^-]$untilHyphen)*-
$untilTwoHyphens = 
    $untilHyphen .
        p()->silent(
            p()->not('-') .
                $untilHyphen
        ) . p()->until->literal('-');
    
// $untilTwoHyphens>?
$commentCompletionExpression =
    $untilTwoHyphens .
        p()->literal('>')->optional;
        
// [^\]]*]([^\]]+])*]+
$rightSquareBrackets = 
    p()->not(']')->until->capture(
        p()->not(']')->literal(']')->more
    ) . p()->any->literal(']')->more;

I didn't get what "beginningOfLine" means!

Got it. It's mixed up. "^" means line start outside sets, inside [sets] as the first char it means a negated set.

A set can only contain literals and ranges. Perhaps ->set('a', 'b', '0-9') would be short while still meaningful, and we can remove the closeSet instruction. Groups could be the same. Every group has another expression inside, so we could have something like ...->capture(p()->set( '/'); Negated sets could simply be named not.

The last regex written as suggested:

<?php
// [^\]]*]([^\]]+])*]+
$rightSquareBrackets =
p()->not(']')->any->capture(
    p()->not(']')->literal(']')->more
)->any->literal(']')->more;

PS: Don't give up on p()! We could have $p() with pure PSR-0 compatibility, or Greppy::autodefine('function_name') based on the autodefine RFC https://wiki.php.net/rfc/autodefine

Thanks for the contribution.

The gist is updated.

About the p() function, yes, I do want to provide that.