require
Otherwise, demands that a library file be included if it hasn't already been included. The file is included via the do-FILE mechanism, which is essentially just a variety of eval() . Has semantics similar to the following subroutine:
Note that the file will not be included twice under the same specified
name. The file must return TRUE as the last statement to indicate
successful execution of any initialization code, so it's customary to
end such a file with ``1;'' unless you're sure it'll return TRUE
otherwise. But it's better just to put the ``1;
'', in case you add more
statements.
If EXPR is a bare word, the require assumes a ``.pm'' extension for you, to make it easy to load standard modules. This form of loading of modules does not risk altering your namespace.
For a yet-more-powerful import facility, see the use and the perlmod manpage .