# NAME

# NAME

Hash::Util::Merge - utility functions for merging hashes

# VERSION

version v0.1.2

# SYNOPSIS

```perl
use Hash::Util::Merge qw/ mergemap /;

my %a = ( x => 1, y => 2 );
my %b = ( x => 3, y => 7 );

my $c = mergemap { $a + $b } \%a, \%b;

# %c = ( x => 4, y => 9 );
```

# DESCRIPTION

This module provides some syntactic sugar for merging simple
hashes with a function.

# EXPORTS

None by default.

## mergemap

```
$hashref = mergemap { fn($a,$b) } \%a, \%b;
```

For each key in the hashes `%a` and `%b`, this function applies the
user-supplied function `fn` to the corresponding values of that key,
in the resulting hash reference.

If a key does not exist in either of the hashes, then it will return
`undef`.

# KNOWN ISSUES

[Readonly](https://metacpan.org/pod/Readonly) hashes, or those with locked keys, may return an error
when merged with a hash that has other keys.

# SEE ALSO

[Hash::Merge](https://metacpan.org/pod/Hash::Merge)

# SOURCE

The development version is on github at [https://github.com/robrwo/Hash-Util-Merge](https://github.com/robrwo/Hash-Util-Merge)
and may be cloned from [git://github.com/robrwo/Hash-Util-Merge.git](git://github.com/robrwo/Hash-Util-Merge.git)

# BUGS

Please report any bugs or feature requests on the bugtracker website
[https://github.com/robrwo/Hash-Util-Merge/issues](https://github.com/robrwo/Hash-Util-Merge/issues)

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.

# AUTHOR

Robert Rothenberg <[email protected]>

This module uses code from [List::Util::PP](https://metacpan.org/pod/List::Util::PP).

This module was developed from work for Science Photo Library
[https://www.sciencephoto.com](https://www.sciencephoto.com).

# CONTRIBUTOR

Mohammad S Anwar <[email protected]>

# COPYRIGHT AND LICENSE

This software is Copyright (c) 2020 by Robert Rothenberg.

This is free software, licensed under:

```
The Artistic License 2.0 (GPL Compatible)
```