home | O'Reilly's CD bookshelfs | FreeBSD | Linux | Cisco | Cisco Exam    

8.16 B::Lint

Provides program checking for Perl programs, equivalent to running Perl with the -w option. Named after the Unix lint program for checking C programs. Invoked as:

perl -MO=Lint[,
program is the name of the Perl program to be checked. The options are separated by commas and follow normal backend option conventions. Most of the options are lint -check options, where each option is a word specifying one lint check. Preceding an option with no- turns off that option. Options specified later override earlier options. There is also one non-lint-check option, -u . Here is the list of available options:


Turns all warnings on.


Warns whenever an array is used in implicit scalar context.


Warns whenever $_ is explicitly used anywhere or whenever it is used as the implicit argument of a print statement.


Warns whenever an operation implicitly reads a Perl special variable.


Warns whenever an operation implicitly writes to a Perl special variable.


Turns off all warnings.


Warns whenever any variable, subroutine, or method name lives in a non-current package but begins with an underscore ( _ ); doesn't warn about an underscore as a single-character name, e.g., $_ .


Warns whenever one of the regular-expression variables $' , $& , or $` is used.

-u Package

Normally checks only the main program code and all subroutines defined in package main ; -u  lets you specify other packages to be checked.


Warns whenever an undefined subroutine is invoked.