App::tracepm - Trace dependencies of your Perl script


This document describes version 0.230 of App::tracepm (from Perl distribution App-tracepm), released on 2020-04-08.


This distribution provides command-line utility called tracepm.




 tracepm(%args) -> [status, msg, payload, meta]

Trace dependencies of your Perl script.

This function is not exported.

Arguments ('*' denotes required arguments):

  • args => array[str]

    Script arguments.

  • cache_prereqscanner => bool (default: 0)

    Whether cache Perl::PrereqScanner{,::Lite} result.

  • core => bool

    Filter only modules that are in core.

  • detail => bool (default: 0)

    Whether to return records instead of just module names.

  • eval => str

    Specify script from command-line instead.

  • method => str (default: "fatpacker")

    Tracing method to use.

    There are several tracing methods that can be used:

    • fatpacker (the default): This method uses the same method that fatpacker trace uses, which is running the script using perl -c then collect the populated %INC. Only modules loaded during compile time are detected.

    • require: This method runs your script normally until it exits. At the start of program, it replaces CORE::GLOBAL::require() with a routine that logs the require() argument to the log file. Modules loaded during runtime is also logged by this method. But some modules might not work, specifically modules that also overrides require() (there should be only a handful of modules that do this though).

    • prereqscanner: This method does not run your Perl program, but statically analyze it using Perl::PrereqScanner. Since it uses PPI, it can be rather slow.

    • prereqscanner_recurse: Like prereqscanner, but will recurse into all non-core modules until they are exhausted. Modules that are not found will be skipped. It is recommended to use the various recurse_exclude_* options options to limit recursion.

    • prereqscanner_lite: This method is like the prereqscanner method, but instead of Perl::PrereqScanner it uses Perl::PrereqScanner::Lite. The latter does not use PPI but use Compiler::Lexer which is significantly faster.

    • prereqscanner_lite_recurse: Like prereqscanner_lite, but recurses.

  • module => perl::modname

    --module MOD is equivalent to --script 'use MOD'.

  • multiple_runs => array[hash]

    Parameter to run script multiple times.

    A more general alternative to using args. Script will be run multiple times, each with setting from element of this option.

    Can be used to reach multiple run pathways and trace more modules.


     [{"args":["-h"]}, # help mode
      {"args":[""], "env":{"COMP_LINE":"cmd x", "COMP_POINT":5}},
  • perl_version => str

    Perl version, defaults to current running version.

    This is for determining which module is core (the list differs from version to version. See Module::CoreList for more details.

  • recurse_exclude => array[str]

    When recursing, exclude some modules.

  • recurse_exclude_core => bool

    When recursing, exclude core modules.

  • recurse_exclude_pattern => array[str]

    When recursing, exclude some module patterns.

  • recurse_exclude_xs => bool

    When recursing, exclude XS modules.

  • script => filename

    Path to script file.

  • trap_script_output => bool

    Trap script output so it does not interfere with trace result.

  • use => array[str]

    Additional modules to "use".

    This is like running:

     perl -MModule1 -MModule2
  • xs => bool

    Filter only modules that are XS modules.

Returns an enveloped result (an array).

First element (status) is an integer containing HTTP status code (200 means OK, 4xx caller error, 5xx function error). Second element (msg) is a string containing error message, or 'OK' if status is 200. Third element (payload) is optional, the actual result. Fourth element (meta) is called result metadata and is optional, a hash that contains extra information.

Return value: (any)


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