NAME
    Data::ZPath - ZPath implementation for Perl

SYNOPSIS
      use Data::ZPath;
      use XML::LibXML;

      my $path = Data::ZPath->new('./foo/bar');
      my $dom  = XML::LibXML->load_xml( string => '<foo><bar>5</bar></foo>' );

      my $result  = $path->first($dom);      # 5
      my @results = $path->all($dom);        # ( 5 )

      my $hashref = { foo => { bar => 6 } };
      my $result2 = $path->first($hashref);  # 6

      $path->each($hashref, sub { $_ *= 2 }); # increments bar -> 12

DESCRIPTION
    Implements the ZPath grammar and core functions described at
    https://zpath.me.

    Key parsing rules from zpath.me:

    *   Paths are UNIX-like segments separated by "/".

    *   Segments can be: "*", "**", ".", "..", "..*", a name, "#n", "name#n",
        a function call, and any segment can have qualifiers "[expr]" (zero or
        more).

    *   Binary operators require whitespace on both sides.

    *   Ternary "? :" requires whitespace around "?" and ":".

    *   Top-level expression may be a comma-separated list of expressions.

METHODS
  new($expr)
    Compile a ZPath expression.

  first($root)
    Evaluate and return the first primitive value.

  all($root)
    Evaluate and return all primitive values.

  evaluate($root)
    Evaluate matches.

    In list context, returns a list of Data::ZPath::Node objects. In scalar
    context, returns a Data::ZPath::NodeList object wrapping those nodes.

    This is the low-level API used by the convenience methods.

  last($root)
    Evaluate and return the last primitive value.

  `each($root, $callback)`
    Evaluate and invoke callback for each matched Perl scalar, aliasing $_ so
    modifications write back.

PACKAGE VARIABLES
    $Data::ZPath::Epsilon
        The desired error tolerance when the zpath `==` and `!=` operators
        compare floating point numbers for equality. Defaults to 1e-08.

        If you need to change this, it is recommended that you use `local` in
        the smallest scope possible.

    $Data::ZPath::UseBigInt
        If true, the number("123...") function will return a Math::BigInt
        object for any numbers too big to be represented accurately by Perl's
        native numeric type. Defaults to true.

    $Data::ZPath::XmlIgnoreWS
        Ignore XML text nodes consisting only of whitespace. Default true.

BUGS
    Please report any bugs to
    <https://github.com/tobyink/p5-data-zpath/issues>.

SEE ALSO
    <https://zpath.me>.

AUTHOR
    Toby Inkster <tobyink@cpan.org>.

COPYRIGHT AND LICENCE
    This software is copyright (c) 2026 by Toby Inkster.

    This is free software; you can redistribute it and/or modify it under the
    same terms as the Perl 5 programming language system itself.

DISCLAIMER OF WARRANTIES
    THIS PACKAGE IS PROVIDED "AS IS" AND WITHOUT ANY EXPRESS OR IMPLIED
    WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
    MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.