Tie::Hash::NamedCapture(3p) Perl Programmers Reference Guide Tie::Hash::NamedCapture(3p)

Tie::Hash::NamedCapture - Named regexp capture buffers

    tie my %hash, "Tie::Hash::NamedCapture";
    # %hash now behaves like %+
    tie my %hash, "Tie::Hash::NamedCapture", all => 1;
    # %hash now access buffers from regexp in $qr like %-

This module is used to implement the special hashes "%+" and "%-", but it can be used to tie other variables as you choose.

When the "all" parameter is provided, then the tied hash elements will be array refs listing the contents of each capture buffer whose name is the same as the associated hash key. If none of these buffers were involved in the match, the contents of that array ref will be as many "undef" values as there are capture buffers with that name. In other words, the tied hash will behave as "%-".

When the "all" parameter is omitted or false, then the tied hash elements will be the contents of the leftmost defined buffer with the name of the associated hash key. In other words, the tied hash will behave as "%+".

The keys of "%-"-like hashes correspond to all buffer names found in the regular expression; the keys of "%+"-like hashes list only the names of buffers that have captured (and that are thus associated to defined values).

This implementation has been moved into the core executable, but you can still load this module for backward compatibility.

perlreapi, re, "Pragmatic Modules" in perlmodlib, "%+" in perlvar, "%-" in perlvar.

2021-03-02 perl v5.36.3