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7.2.76 vars - Predeclare Global Variable Names

use vars qw($frob @mung %seen);

This module predeclares all variables whose names are in the list, allowing you to use them under use strict , and disabling any typo warnings.

Packages such as the AutoLoader and SelfLoader that delay loading of subroutines within packages can create problems with file-scoped lexicals defined using my . This is because they move the subroutines outside the scope of the lexical variables. While the use vars pragma cannot duplicate the effect of file-scoped lexicals (total transparency outside of the file), it can act as an acceptable substitute by pre-declaring global symbols, ensuring their availability to the routines whose loading was delayed.

See also the subs module.


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