Params::ValidationCompiler - Build an optimized subroutine parameter validator once, use it forever
version 0.20
use Types::Standard qw( Int Str ); use Params::ValidationCompiler qw( validation_for ); { my $validator = validation_for( params => { foo => { type => Int }, bar => { type => Str, optional => 1, }, baz => { type => Int, default => 42, }, }, ); sub foo { my %args = $validator->(@_); } } { my $validator = validation_for( params => [ { type => Int }, { type => Str, optional => 1, }, ], ); sub bar { my ( $int, $str ) = $validator->(@_); } } { my $validator = validation_for( params => [ foo => { type => Int }, bar => { type => Str, optional => 1, }, ], named_to_list => 1, ); sub baz { my ( $foo, $bar ) = $validator->(@_); } }
This is still fairly alpha. Things could change. You have been warned.
This module creates a customized, highly efficient parameter checking subroutine. It can handle named or positional parameters, and can return the parameters as key/value pairs or a list of values.
In addition to type checks, it also supports parameter defaults, optional parameters, and extra "slurpy" parameters.
This module has two options exports, validation_for and source_for. Both of these subs accept the same options:
validation_for
source_for
params
An arrayref or hashref containing a parameter specification.
If you pass a hashref then the generated validator sub will expect named parameters. The params value should be a hashref where the parameter names are keys and the specs are the values.
If you pass an arrayref and named_to_list is false, the validator will expect positional params. Each element of the params arrayref should be a parameter spec.
named_to_list
If you pass an arrayref and named_to_list is false, the validator will expect named params, but will return a list of values. In this case the arrayref should contain a list of key/value pairs, where parameter names are the keys and the specs are the values.
Each spec can contain either a boolean or hashref. If the spec is a boolean, this indicates required (true) or optional (false).
The spec hashref accepts the following keys:
type
A type object. This can be a Moose type (from Moose or MooseX::Types), a Type::Tiny type, or a Specio type.
If the type has coercions, those will always be used.
default
This can either be a simple (non-reference) scalar or a subroutine reference. The sub ref will be called without any arguments (for now).
optional
A boolean indicating whether or not the parameter is optional. By default, parameters are required unless you provide a default.
slurpy
If this is a simple true value, then the generated subroutine accepts additional arguments not specified in params. By default, extra arguments cause an exception.
You can also pass a type constraint here, in which case all extra arguments must be values of the specified type.
If this is true, the generated subroutine will expect a list of key-value pairs or a hashref and it will return a list containing only the values. params must be a arrayref of key-value pairs in the order of which the values should be returned.
You cannot combine slurpy with named_to_list as there is no way to know how the order in which extra values should be returned.
This returns a subroutine that implements the specific parameter checking. This subroutine expects to be given the parameters to validate in @_. If all the parameters are valid, it will return the validated parameters (with defaults as appropriate), either as a list of key-value pairs or as a list of just values. If any of the parameters are invalid it will throw an exception.
@_
For validators expected named params, the generated subroutine accepts either a list of key-value pairs or a single hashref. Otherwise the validator expects a list of values.
For now, you must shift off the invocant yourself.
This subroutine accepts an additional parameter:
name
If this is given, then the generated subroutine will be named using Sub::Util. This is strongly recommended as it makes it possible to distinguish different check subroutines when profiling or in stack traces.
Note that you must install Sub::Util yourself separately, as it is not required by this distribution, in order to avoid requiring a compiler.
name_is_optional
If this is true, then the name is ignored when Sub::Util is not installed. If this is false, then passing a name when Sub::Util cannot be loaded causes an exception.
Sub::Util
This is useful for CPAN modules where you want to set a name if you can, but you do not want to add a prerequisite on Sub::Util.
This returns a two element list. The first is a string containing the source code for the generated sub. The second is a hashref of "environment" variables to be used when generating the subroutine. These are the arguments that are passed to Eval::Closure.
Bugs may be submitted through the RT bug tracker (or bug-params-validationcompiler@rt.cpan.org).
I am also usually active on IRC as 'autarch' on irc://irc.perl.org.
irc://irc.perl.org
If you'd like to thank me for the work I've done on this module, please consider making a "donation" to me via PayPal. I spend a lot of free time creating free software, and would appreciate any support you'd care to offer.
Please note that I am not suggesting that you must do this in order for me to continue working on this particular software. I will continue to do so, inasmuch as I have in the past, for as long as it interests me.
Similarly, a donation made in this way will probably not make me work on this software much more, unless I get so many donations that I can consider working on free software full time (let's all have a chuckle at that together).
To donate, log into PayPal and send money to autarch@urth.org, or use the button at http://www.urth.org/~autarch/fs-donation.html.
Dave Rolsky <autarch@urth.org>
Gregory Oschwald <goschwald@maxmind.com>
This software is Copyright (c) 2016 by Dave Rolsky.
This is free software, licensed under:
The Artistic License 2.0 (GPL Compatible)
To install Params::ValidationCompiler, copy and paste the appropriate command in to your terminal.
cpanm
cpanm Params::ValidationCompiler
CPAN shell
perl -MCPAN -e shell install Params::ValidationCompiler
For more information on module installation, please visit the detailed CPAN module installation guide.