Sah::Schema::percent_str - A number in percent form


This document describes version 0.012 of Sah::Schema::percent_str (from Perl distribution Sah-Schemas-Str), released on 2022-09-22.


Sample data and validation results against this schema

 ""  # INVALID (No percent sign)

 1  # INVALID (No percent sign)

 "1%"  # valid

 "1 %"  # INVALID (Whitespace before percent sign is currently not allowed)

 "-1.23%"  # valid

 "%"  # INVALID (Percent sign only)

Using with Data::Sah

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

 use Data::Sah qw(gen_validator);
 my $validator = gen_validator("percent_str*");
 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_str", {return_type=>'str_errmsg'});
 my $errmsg = $validator->($data);
 # a sample valid data
 $data = "1%";
 my $errmsg = $validator->($data); # => ""
 # a sample invalid data
 $data = 1;
 my $errmsg = $validator->($data); # => "Must match regex pattern qr(\\A(?^:[+-]?(?:[0-9]+(?:\\.[0-9]*)?|[0-9]*\\.[0-9]+))%\\z)"

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_str", {return_type=>'str_errmsg+val'});
 my $res = $validator->($data); # [$errmsg, $validated_val]
 # a sample valid data
 $data = "1%";
 my $res = $validator->($data); # => ["","1%"]
 # a sample invalid data
 $data = 1;
 my $res = $validator->($data); # => ["Must match regex pattern qr(\\A(?^:[+-]?(?:[0-9]+(?:\\.[0-9]*)?|[0-9]*\\.[0-9]+))%\\z)",1]

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_str*");

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/
 our %SPEC;
 $SPEC{myfunc} = {
     v => 1.1,
     summary => 'Routine to do blah ...',
     args => {
         arg1 => {
             summary => 'The blah blah argument',
             schema => ['percent_str*'],
 sub myfunc {
     my %args = @_;

 # in
 use Perinci::CmdLine::Any;

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

 % ./ --version

 % ./ --arg1 ...


This schema accepts floating number followed by percent sign. Unlike the percent schema from Sah::Schemas::Float, The percent sign will not be removed nor the number be converted to decimal (e.g. 50% to 0.5).


Please visit the project's homepage at


Source repository is at




perlancar <>


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.


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

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.


Please report any bugs or feature requests on the bugtracker website

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.