Data::Visitor::Tiny - Recursively walk data structures

    version 0.001

        use Data::Visitor::Tiny;

        my $hoh = {
            a => { b => 1, c => 2 },
            d => { e => 3, f => 4 },

        # print leaf (non-ref) values on separate lines (1 2 3 4)
        visit( $hoh, sub { return if ref; say } );

        # transform leaf value for a given key
            sub {
                my ( $key, $valueref ) = @_;
                $$valueref = "replaced" if $key eq 'e';
        say $hoh->{d}{e}; # "replaced"

    This module provides a simple framework for recursively iterating over a
    data structure of hashrefs and/or arrayrefs.

        visit( $ref, sub { ... } );

    The "visit" function takes a hashref or arrayref and recursively visits
    all values via pre-order traversal, calling the provided callback for
    each value. Only hashrefs and arrayrefs are traversed; objects, even if
    they override hash or array dereference, are only ever treated as
    values. Hash keys are sorted lexicographically before iteration,
    ensuring consistent visitation order in the face of Perl's hash order

    Within the callback, the $_ variable is set to the value of the node.
    The callback also receives three arguments: $key, $valueref, and
    $context. The $key is the hash key or array index of the value. The
    $valueref is a scalar reference to the value; use it to modify the value
    in place. The $context is a hashref for tracking state throughout the
    visiting process. Context keys beginning with '_' are reserved for
    "Data::Visitor::Tiny"; you may store whatever other keys/values you
    need. The only key provided currently is "_depth", which starts at 0 and
    reflects how deep the visitor has recursed.

    The "visit" function returns the context object.

    *   Data::Visitor

    *   Data::Visitor::Lite

    *   Data::Rmap

    *   Data::Traverse

  Bugs / Feature Requests
    Please report any bugs or feature requests through the issue tracker at
    <>. You will be
    notified automatically of any progress on your issue.

  Source Code
    This is open source software. The code repository is available for
    public review and contribution under the terms of the license.


      git clone

    David Golden <>

    This software is Copyright (c) 2018 by David Golden.

    This is free software, licensed under:

      The Apache License, Version 2.0, January 2004