# B::Hooks::OP::Check - Wrap OP check callbacks - perldoc - [phpMan]

## NAME
    [B::Hooks::OP::Check](https://www.chedong.com/phpMan.php/perldoc/B%3A%3AHooks%3A%3AOP%3A%3ACheck/markdown) - Wrap OP check callbacks

## VERSION
    version 0.22

## SYNOPSIS
        # include "hook_op_check.h"

        STATIC OP *my_const_check_op (pTHX_ OP *op, void *user_data) {
            /* ... */
            return op;
        }

        STATIC hook_op_check_id my_hook_id = 0;

        void
        setup ()
            CODE:
                my_hook_id = hook_op_check (OP_CONST, my_const_check_op, NULL);

        void
        teardown ()
            CODE:
                hook_op_check_remove (OP_CONST, my_hook_id);

## DESCRIPTION
    This module provides a C API for XS modules to hook into the callbacks of "PL_check".

    [ExtUtils::Depends](https://www.chedong.com/phpMan.php/perldoc/ExtUtils%3A%3ADepends/markdown) is used to export all functions for other XS modules to use. Include the
    following in your Makefile.PL:

        my $pkg = [ExtUtils::Depends](https://www.chedong.com/phpMan.php/perldoc/ExtUtils%3A%3ADepends/markdown)->new('[Your::XSModule](https://www.chedong.com/phpMan.php/perldoc/Your%3A%3AXSModule/markdown)', '[B::Hooks::OP::Check](https://www.chedong.com/phpMan.php/perldoc/B%3A%3AHooks%3A%3AOP%3A%3ACheck/markdown)');
        WriteMakefile(
            ... # your normal makefile flags
            $pkg->get_makefile_vars,
        );

    Your XS module can now include "hook_op_check.h".

## TYPES
  typedef OP *(*hook_op_check_cb) (pTHX_ OP *, void *);
    Type that callbacks need to implement.

  typedef UV hook_op_check_id
    Type to identify a callback.

## FUNCTIONS
  hook_op_check_id hook_op_check (opcode type, hook_op_check_cb cb, void *user_data)
    Register the callback "cb" to be called after the "PL_check" function for opcodes of the given
    "type". "user_data" will be passed to the callback as the last argument. Returns an id that can
    be used to remove the callback later on.

  void *hook_op_check_remove (opcode type, hook_op_check_id id)
    Remove the callback identified by "id". Returns the user_data that the callback had.

## SUPPORT
    Bugs may be submitted through the RT bug tracker
    <<https://rt.cpan.org/Public/Dist/Display.html?Name=B-Hooks-OP-Check>> (or
    <bug-B-Hooks-OP-Check@rt.cpan.org> <mailto:<bug-B-Hooks-OP-Check@rt.cpan.org>>).

## AUTHOR
    Florian Ragwitz <<rafl@debian.org>>

## CONTRIBUTORS
    *   Karen Etheridge <<ether@cpan.org>>

    *   Zefram <<zefram@fysh.org>>

    *   Alexandr Ciornii <<alexchorny@gmail.com>>

## COPYRIGHT AND LICENCE
    This software is copyright (c) 2008 by Florian Ragwitz.

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