Perinci::CmdLine::Manual(3) Perinci::CmdLine manual


This document describes version 1.48 of Perinci::CmdLine::Manual (from Perl distribution Perinci-CmdLine), released on 2015-10-22.


Perinci::CmdLine is a command-line application framework. It parses command-line options and dispatches to one of your specified Perl functions, passing the command-line options and arguments to the function. It accesses functions via Riap protocol (using the Perinci::Access Riap client library) so you can use remote functions transparently. Features:
  • Command-line options parsing

    Non-scalar arguments (array, hash, other nested) can also be passed as JSON or YAML. For example, if the "tags" argument is defined as 'array', then all of below are equivalent:

     % mycmd --tags-yaml '[foo, bar, baz]'
     % mycmd --tags-yaml '["foo","bar","baz"]'
     % mycmd --tags foo --tags bar --tags baz
  • Help message (utilizing information from metadata, supports translation)

     % mycmd --help
     % mycmd -h
     % mycmd -?
  • Tab completion for various shells (including completion from remote code)

    Example for bash:

     % complete -C mycmd mycmd
     % mycmd --he<tab> ; # --help
     % mycmd s<tab>    ; # sub1, sub2, sub3 (if those are the specified subcommands)
     % mycmd sub1 -<tab> ; # list the options available for sub1 subcommand
  • Undo/redo/history

    If the function supports transaction (see Rinci::Transaction, Riap::Transaction) the framework will setup transaction and provide command to do undo (--undo) and redo (--redo) as well as seeing the undo/transaction list (--history) and clearing the list (--clear-history).

  • Version (--version, -v)
  • List available subcommands (--subcommands)
  • Configurable output format (--format, --format-options)

    By default "yaml", "json", "text", "text-simple", "text-pretty" are recognized.


Perinci::CmdLine is very function-oriented (and very not object-oriented, on purpose). You write your ``business logic'' in a function (of course, you are free to subdivide or delegate to other functions, but there must be one main function for a single-subcommand CLI application, or one function for each subcommand in a multiple-subcommand CLI application.

 sub cliapp {

You annotate the function with Rinci metadata, where you describe what arguments (and command-line aliases, if any) the function (program) accepts, the summary and description of those arguments, and several other aspects as necessary.

 $SPEC{cliapp} = {
     v => 1.1,
     summary => 'A program to do blah blah',
     args => {
         foo => {
             summary => 'foo argument',
             req => 1,
             pos => 0,
             cmdline_aliases => {f=>{}},
         bar => { ... },
 sub cliapp {

Finally, you ``run'' your function:

 use Perinci::CmdLine::Any;
 Perinci::CmdLine::Any->new(url => '/main/cliapp')->run;

For a multi-subcommand application:

     url => '/main/cliapp',
     subcommands => {
         sc1 => { url => '/main/do_sc1' },
         sc2 => { url => '/main/do_sc2' },

That's it. Command-line option parsing, help message, as well as tab completion will work without extra effort.

To run a remote function, you can simply specify a remote URL, e.g. "". All the features like options parsing, help/usage, as well as tab completion will work with remote functions as well.


Below is the description of how the framework determines what action and which function to call.



Logging is done with Log::Any::IfLOG (for producing). For displaying logs, PC::Classic uses Log::Any::App currently which supports multiple outputs (screen, file, etc) while PC::Lite currently uses Log::Any::Adapter::Screen which only supports displaying to screen.

Loading Log::Any adapters adds to startup overhead time, so the framework tries to be smart when determining whether or not to do logging output. Here are the order of rules being used:

  • If LOG environment is undefined or false, turn off logging

    So you need to use LOG=1 to turn on logging.

  • If running shell completion ("COMP_LINE" is defined), output is off

    Normally, shell completion does not need to show log output.

  • If subcommand's "log" setting is defined, use that

    This allows you, e.g. to turn off logging by default for subcommands that need faster startup time.

  • [Classic] If action metadata's default_log setting is defined, use that

    For example, actions like "help", "list", and "version" has "default_log" set to 0, for faster startup time.

  • Use log attribute setting

[Classic] UTF8 OUTPUT

By default, "binmode(STDOUT, ":utf8")" is issued if utf8 output is desired. This is determined by, in order:
  • Use setting from environment UTF8, if defined.

    This allows you to force-disable or force-enable utf8 output.

  • Use setting from action metadata, if defined.

    Some actions like help, list, and version output translated text, so they have their "use_utf8" metadata set to 1.

  • Use setting from subcommand, if defined.
  • Use setting from "use_utf8" attribute.

    This attribute comes from SHARYANTO::Role::TermAttrs, its default is determined from UTF8 environment as well as terminal's capabilities.


By default colors are used, but if terminal is detected as not having color support, they are turned off. You can also turn off colors by setting COLOR=0 or using PERINCI_CMDLINE_COLOR_THEME=Default::no_color.


Configuration files are read to preset the value of arguments, before potentially overridden/merged with command-line options. Configuration files are in IOD format, which is basically "INI" with some extra features.

By default, configuration files are searched in "/etc" and home directory, with the name of program_name + ".conf". If multiple files are found, the contents are merged together.

If user wants to use a custom configuration file, she can issue "--config-path" command-line option.

If user does not want to read configuration file, she can issue "--noconfig" command-line option.

The configuration file's section corresponds to subcommand names and/or profile names. Profiles are ways to specify multiple sets/cases/scenarios in a single configuration file.

Example 1 (without any profile or subcommand):

 ; prog.conf

When executing program (the comments will show what arguments are set):

 % prog; # {foo=>1, bar=>2}
 % prog --foo 10; # {foo=>10, bar=>2}

Example 2 (with profiles):

 ; prog.conf

When executing program:

 % prog; # {}
 % prog --config-profile profile1; # {foo=>1, bar=>2}
 % prog --config-profile profile2; # {foo=>10, bar=>20}

Example 3 (with subcommands):

 ; prog.conf

When executing program:

 % prog subcommand1; # {foo=>1, bar=>2}
 % prog subcommand2; # {baz=>3, qux=>4}

Example 4 (with subcommands and profiles):

 ; prog.conf
 [subcommand1 profile=profile1]
 [subcommand1 profile=profile2]

When executing program:

 % prog subcommand1 --config-profile profile1; # {foo=>1, bar=>2}
 % prog subcommand1 --config-profile profile2; # {foo=>10, bar=>20}


This section describes how Perinci::CmdLine parses command-line options/arguments into function arguments. Command-line option parsing is implemented by Perinci::Sub::GetArgs::Argv.

For boolean function arguments, use "--arg" to set "arg" to true (1), and "--noarg" to set "arg" to false (0). A flag argument ("[bool => {is=>1}]") only recognizes "--arg" and not "--noarg". For single letter arguments, only "-X" is recognized, not "--X" nor "--noX".

For string and number function arguments, use "--arg VALUE" or "--arg=VALUE" (or "-X VALUE" for single letter arguments) to set argument value. Other scalar arguments use the same way, except that some parsing will be done (e.g. for date type, --arg 1343920342 or --arg '2012-07-31' can be used to set a date value, which will be a DateTime object.) (Note that date parsing will be done by Data::Sah and currently not implemented yet.)

For arguments with type array of scalar, a series of "--arg VALUE" is accepted, a la Getopt::Long:

 --tags tag1 --tags tag2 ; # will result in tags => ['tag1', 'tag2']

For other non-scalar arguments, also use "--arg VALUE" or "--arg=VALUE", but VALUE will be attempted to be parsed using JSON, and then YAML. This is convenient for common cases:

 --aoa  '[[1],[2],[3]]'  # parsed as JSON
 --hash '{a: 1, b: 2}'   # parsed as YAML

For explicit JSON parsing, all arguments can also be set via --ARG-json. This can be used to input undefined value in scalars, or setting array value without using repetitive "--arg VALUE":

 --str-json 'null'    # set undef value
 --ary-json '[1,2,3]' # set array value without doing --ary 1 --ary 2 --ary 3
 --ary-json '[]'      # set empty array value

Likewise for explicit YAML parsing:

 --str-yaml '~'       # set undef value
 --ary-yaml '[a, b]'  # set array value without doing --ary a --ary b
 --ary-yaml '[]'      # set empty array value

Submetadata. Arguments from submetadata will also be given respective command-line options (and aliases) with prefixed names. For example this function metadata:

     v => 1.1,
     args => {
         foo => {schema=>'str*'},
         bar => {
             schema => 'hash*',
             meta => {
                 v => 1.1,
                 args => {
                     baz => {schema=>'str*'},
                     qux => {
         quux => {
             schema => 'array*',
             element_meta => {
                 v => 1.1,
                 args => {
                     corge => {schema=>'str*', cmdline_aliases=>{C=>{}},
                     grault => {schema=>'str*'},

You can specify on the command-line:

 % prog --foo val \
     --bar-baz val --bar-qux val \
     --quux-corge 11 \
     --quux-corge 21 --quux-grault 22 \
     --quux-C 31

The resulting argument will be:

     foo => 'val',
     bar => {
         baz => 'val',
         qux => 'val',
     quux => [
         {corge=>21, grault=>22},

For more examples on argument submetadata, see Perinci::Examples::SubMeta.


The framework can detect when "COMP_LINE" and "COMP_POINT" environment variables (set by bash when completing using external command) are set and then answer the completion. In bash, activating tab completion for your script is as easy as (assuming your script is already in PATH):

 % complete -C yourscript yourscript

That is, your script can complete itself. The above command can be put in "~/.bashrc". But it is recommended that you use shcompgen instead (see below).

Tcsh uses "COMMAND_LINE" instead. The framework can also detect that.

For other shells: some shells can emulate bash (like zsh) and for some other (like fish) you need to generate a set of "complete" commands for each command-line option.

"shcompgen" is a CLI tool that can detect all scripts in PATH if they are using Perinci::CmdLine (as well as a few other frameworks) and generate shell completion scripts for them. It supports several shells. Combined with Dist::Zilla::Plugin::GenShellCompletion, you can make it so that users installing your distribution can immediately/automatically activate tab completion for your scripts.


For functions that express that they do progress updating (by setting their "progress" feature to true), Perinci::CmdLine will setup an output, currently either Progress::Any::Output::TermProgressBar if program runs interactively, or Progress::Any::Output::LogAny if program doesn't run interactively.


Please visit the project's homepage at <>.


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 <[email protected]>


This software is copyright (c) 2015 by [email protected].

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