Hidden features of Perl?

Answer 1

Special code blocks such as BEGIN, CHECK and END. They come from Awk, but work differently in Perl, because it is not record-based.

The BEGIN block can be used to specify some code for the parsing phase; it is also executed when you do the syntax-and-variable-check perl -c. For example, to load in configuration variables:

BEGIN {
    eval {
        require 'config.local.pl';
    };
    if ($@) {
        require 'config.default.pl';
    }
}