B::Lint(3) Perl Programmers Reference Guide B::Lint(3)NAMEB::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 the perlre manpage 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.
2001-02-22 perl v5.6.1 B::Lint(3)
