NAME

Sah::Schema::percent - A float

VERSION

This document describes version 0.013 of Sah::Schema::percent (from Perl distribution Sah-Schemas-Float), released on 2022-10-20.

SYNOPSIS

Sample data and validation results against this schema

 0  # valid, becomes 0

 0.5  # valid, becomes 0.005

 5  # valid, becomes 0.05

 "5%"  # valid, becomes 0.05

Using with Data::Sah

To check data against this schema (requires Data::Sah):

 use Data::Sah qw(gen_validator);
 my $validator = gen_validator("percent*");
 say $validator->($data) ? "valid" : "INVALID!";

The above schema returns a boolean result (true if data is valid, false if otherwise). To return an error message string instead (empty string if data is valid, a non-empty error message otherwise):

 my $validator = gen_validator("percent", {return_type=>'str_errmsg'});
 my $errmsg = $validator->($data);
 
 # a sample valid data
 $data = "5%";
 my $errmsg = $validator->($data); # => ""

Often a schema has coercion rule or default value, so after validation the validated value is different. To return the validated (set-as-default, coerced, prefiltered) value:

 my $validator = gen_validator("percent", {return_type=>'str_errmsg+val'});
 my $res = $validator->($data); # [$errmsg, $validated_val]
 
 # a sample valid data
 $data = "5%";
 my $res = $validator->($data); # => ["",0.05]

Data::Sah can also create validator that returns a hash of detailed error message. Data::Sah can even create validator that targets other language, like JavaScript, from the same schema. Other things Data::Sah can do: show source code for validator, generate a validator code with debug comments and/or log statements, generate human text from schema. See its documentation for more details.

Using with Params::Sah

To validate function parameters against this schema (requires Params::Sah):

 use Params::Sah qw(gen_validator);

 sub myfunc {
     my @args = @_;
     state $validator = gen_validator("percent*");
     $validator->(\@args);
     ...
 }

Using with Perinci::CmdLine::Lite

To specify schema in Rinci function metadata and use the metadata with Perinci::CmdLine (Perinci::CmdLine::Lite) to create a CLI:

 # in lib/MyApp.pm
 package
   MyApp;
 our %SPEC;
 $SPEC{myfunc} = {
     v => 1.1,
     summary => 'Routine to do blah ...',
     args => {
         arg1 => {
             summary => 'The blah blah argument',
             schema => ['percent*'],
         },
         ...
     },
 };
 sub myfunc {
     my %args = @_;
     ...
 }
 1;

 # in myapp.pl
 package
   main;
 use Perinci::CmdLine::Any;
 Perinci::CmdLine::Any->new(url=>'/MyApp/myfunc')->run;

 # in command-line
 % ./myapp.pl --help
 myapp - Routine to do blah ...
 ...

 % ./myapp.pl --version

 % ./myapp.pl --arg1 ...

Using with Type::Tiny

To create a type constraint and type library from a schema:

 package My::Types {
     use Type::Library -base;
     use Type::FromSah qw( sah2type );

     __PACKAGE__->add_type(
         sah2type('$sch_name*', name=>'Percent')
     );
 }

 use My::Types qw(Percent);
 Percent->assert_valid($data);

DESCRIPTION

This type is basically float, with str_as_percent coerce rule. So the percent sign is optional, but the number is always interpreted as percent, e.g. "1" is interpreted as 1% (0.01).

In general, instead of using this schema, I recommend just using the float type (which by default includes coercion rule to convert from percent notation e.g. '1%' -> 0.01). Use this schema if your argument really needs to be expressed in percents.

HOMEPAGE

Please visit the project's homepage at https://metacpan.org/release/Sah-Schemas-Float.

SOURCE

Source repository is at https://github.com/perlancar/perl-Sah-Schemas-Float.

SEE ALSO

Sah::Schema::percent_str

AUTHOR

perlancar <perlancar@cpan.org>

CONTRIBUTING

To contribute, you can send patches by email/via RT, or send pull requests on GitHub.

Most of the time, you don't need to build the distribution yourself. You can simply modify the code, then test via:

 % prove -l

If you want to build the distribution (e.g. to try to install it locally on your system), you can install Dist::Zilla, Dist::Zilla::PluginBundle::Author::PERLANCAR, Pod::Weaver::PluginBundle::Author::PERLANCAR, and sometimes one or two other Dist::Zilla- and/or Pod::Weaver plugins. Any additional steps required beyond that are considered a bug and can be reported to me.

COPYRIGHT AND LICENSE

This software is copyright (c) 2022, 2020, 2019, 2018 by perlancar <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.

BUGS

Please report any bugs or feature requests on the bugtracker website https://rt.cpan.org/Public/Dist/Display.html?Name=Sah-Schemas-Float

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.