B::Lint(t) Perl Programmers Reference Guide B::Lint(t) NAME B::Lint - Perl lint SYNOPSIS perl -MO=Lint[,OPTIONS] foo.pl DESCRIPTION The B::Lint module is equivalent to an extended version of the -w option of perl. It is named after the program lint which carries out a similar process for C programs. OPTIONS AND LINT CHECKS Option words are separated by commas (not whitespace) and follow the usual conventions of compiler backend options. Following any options (indicated by a leading -) come lint check arguments. Each such argument (apart from the spe- cial all and none options) is a word representing one pos- sible lint check (turning on that check) or is no-foo (turning off that check). Before processing the check arguments, a standard list of checks is turned on. Later options override earlier ones. Available options are: context Produces a warning whenever an array is used in an implicit scalar context. For example, both of the lines $foo = length(@bar); $foo = @bar; will elicit a warning. Using an explicit B<scalar()> silences the warning. For example, $foo = scalar(@bar); implicit-read and implicit-write These options produce a warning whenever an opera- tion implicitly reads or (respectively) writes to one of Perl's special variables. For example, implicit-read will warn about these: /foo/; and implicit-write will warn about these: s/foo/bar/; Both implicit-read and implicit-write warn about this: for (@a) { ... } dollar-underscore This option warns whenever $_ is used either explicitly anywhere or as the implicit argument of a print statement. private-names This option warns on each use of any variable, subroutine or method name that lives in a non-cur- rent package but begins with an underscore ("_"). Warnings aren't issued for the special case of the single character name "_" by itself (e.g. $_ and @_). undefined-subs This option warns whenever an undefined subroutine is invoked. This option will only catch explic- itly invoked subroutines such as "foo()" and not indirect invocations such as "&$subref()" or "$obj->meth()". Note that some programs or modules delay definition of subs until runtime by means of the AUTOLOAD mechanism. regexp-variables This option warns whenever one of the regexp vari- ables $', $& or $' is used. Any occurrence of any of these variables in your program can slow your whole program down. See perlre for details. all Turn all warnings on. none Turn all warnings off. NON LINT-CHECK OPTIONS -u Package Normally, Lint only checks the main code of the program together with all subs defined in package main. The -u option lets you include other package names whose subs are then checked by Lint. BUGS This is only a very preliminary version. AUTHOR Malcolm Beattie, mbeattie@sable.ox.ac.uk. perl v5.6.1 2001-02-23 B::Lint(t)