/ 
Sah-Schemas-Float-0.013
River stage one • 6 direct dependents • 6 total dependents
/ Sah::Schema::percent

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.