Sah::Schema::filename - Filesystem file name


This document describes version 0.016 of Sah::Schema::filename (from Perl distribution Sah-Schemas-Path), released on 2021-07-17.


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

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

 # Data::Sah can also create validator that returns nice error message string
 # and/or coerced value. Data::Sah can even create validator that targets other
 # language, like JavaScript. All from the same schema. See its documentation
 # for more details.

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

 use Params::Sah qw(gen_validator);

 sub myfunc {
     my @args = @_;
     state $validator = gen_validator("filename*");

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

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

 # in
 package main;
 use Perinci::CmdLine::Any;

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

 % ./ --version

 % ./ --arg1 ...

Sample data:

 ""  # INVALID

 "foo"  # valid

 "foo/bar"  # valid


This schema is basically string with some checks and prefilters. Why use this schema instead of plain ol' str? Mainly to give you the ability to change tilde to user's home directory, e.g. ~/foo.txt into /home/someuser/foo.txt. Normally this expansion is done by a Unix shell, but sometimes your program receives an unexpanded path, e.g. when you get it from some config file.

See also more OS-specific schemas like filename::unix, which adds some more checks (e.g. filename cannot contain forward slash and each component cannot be longer than 255 characters) and preprocessing (e.g. stripping extraneous slashes like foo//bar into foo/bar.

What's the difference between this schema and dirname? The default completion rule. This schema's completion by default only includes files and not directories.


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Source repository is at


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.


perlancar <>


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