NAME
Data::Transmute - Transmute (transform) data structure using rules data
VERSION
This document describes version 0.030 of Data::Transmute (from Perl distribution Data-Transmute), released on 2019-07-24.
SYNOPSIS
use Data::Transmute qw(
transmute_data
reverse_rules
);
transmute_data(
data => \@data,
rules => [
# this rule only applies when data is a hash, when data is not a hash
# this will will do nothing. create a single new hash key, error if key
# already exists.
[create_hash_key => {name=>'foo', value=>1}],
# create another hash key, but this time ignore/noop if key already
# exists (ignore=1). this is like INSERT IGNORE in SQL.
[create_hash_key => {name=>'bar', value=>2, ignore=>1}],
# create yet another key, this time replace existing keys (replace=1).
# this is like REPLACE INTO in SQL.
[create_hash_key => {name=>'baz', value=>3, replace=>1}],
# this rule only applies when data is a hash, when data is not a hash
# this will will do nothing. rename a single key, error if old name
# doesn't exist or new name exists.
[rename_hash_key => {from=>'qux', to=>'quux'}],
# rename another key, but this time ignore if old name doesn't exist
# (ignore=1) or if new name already exists (replace=1)
[rename_hash_key => {from=>'corge', to=>'grault', ignore_missing_from=>1, replace=>1}],
# this rule only applies when data is a hash, when data is not a hash
# this will will do nothing. delete a single key, will noop if key
# already doesn't exist.
[delete_hash_key => {name=>'garply'}],
# this rule only applies when data is an arrayref, when data is not a
# array this will will do nothing. for each array element, apply
# transmute rules to it.
[transmute_array_elems => {rules => [...]}],
# this rule only applies when data is a hashref, when data is not a
# hash this will will do nothing. for each hash value, apply transmute
# rules to it.
[transmute_hash_values => {rules => [...]}],
],
);DESCRIPTION
This module provides routines to transmute (transform) a data structure in-place using rules which is another data structure (an arrayref of rule specifications).
One use-case for this module is to convert/upgrade configuration files.
RULES
Rules is an array of rule specifications.
Each rule specification: [$funcname, \%args]
\%args: a special arg will be inserted: data.
FUNCTIONS
transmute_data
Usage:
$data = transmute_data(%args)Transmute data structure, die on failure. Input data is specified in the data argument, which will be modified in-place (so you'll need to clone it first if you don't want to modify the original data). Rules is specified in rules argument.
reverse_rules
Usage:
my $reverse_rules = reverse_rules(rules => [...]);Create a reverse rules, die on failure.
TODOS
Check arguments (DZP:Rinci::Wrap?).
Undo?
Function to mass rename keys (by regex substitution, prefix, custom Perl code, ...).
Function to mass delete keys (by regex, prefix, ...).
HOMEPAGE
Please visit the project's homepage at https://metacpan.org/release/Data-Transmute.
SOURCE
Source repository is at https://github.com/perlancar/perl-Data-Transmute.
BUGS
Please report any bugs or feature requests on the bugtracker website https://rt.cpan.org/Public/Dist/Display.html?Name=Data-Transmute
When submitting a bug or request, please include a test-file or a patch to an existing test-file that illustrates the bug or desired feature.
SEE ALSO
Hash::Transform is similar in concept. It allows transforming a hash using rules encoded in a hash. However, the rules only allow for simpler transformations: rename a key, create a key with a specified value, create a key that from a string-based join of other keys/strings. For more complex needs, you'll have to supply a coderef to do the transformation yourself manually. Another thing I find limiting is that the rules is a hash, which means there is no way to specify order of processing. And of course, you cannot transform non-hash data.
Config::Model, which you can also use to convert/upgrade configuration files. But I find this module slightly too heavyweight for the simpler needs that I have, hence I created Data::Transmute.
AUTHOR
perlancar <perlancar@cpan.org>
COPYRIGHT AND LICENSE
This software is copyright (c) 2019, 2015 by perlancar@cpan.org.
This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.