perl-Hook-LexWrap

Lexically scoped subroutine wrappers

Hook::LexWrap allows you to install a pre- or post-wrapper (or both) around an existing subroutine. Unlike other modules that provide this capacity (e.g. Hook::PreAndPost and Hook::WrapSub), Hook::LexWrap implements wrappers in such a way that the standard 'caller' function works correctly within the wrapped subroutine. To install a prewrappers, you write: use Hook::LexWrap; wrap 'subroutine_name', pre => \&some_other_sub; The first argument to 'wrap' is a string containing the name of the subroutine to be wrapped (or the typeglob containing it, or a reference to it). The subroutine name may be qualified, and the subroutine must already be defined. The second argument indicates the type of wrapper being applied and must be either ''pre'' or ''post''. The third argument must be a reference to a subroutine that implements the wrapper. To install a post-wrapper, you write: wrap 'subroutine_name', post => \&yet_another_sub; To install both at once: wrap 'subroutine_name', pre => \&some_other_sub, post => \&yet_another_sub; or: wrap *subroutine_name, post => \&yet_another_sub, # order in which wrappers are pre => \&some_other_sub; # specified doesn't matter Once they are installed, the pre- and post-wrappers will be called before and after the subroutine itself, and will be passed the same argument list. The pre- and post-wrappers and the original subroutine also all see the same (correct!) values from 'caller' and 'wantarray'.