Best Practice For PERL

#!c:\>perl\bin\perl.exe
use strict;
use warnings;
use diagnostics;

use strict

  • Generates an error if you use symbolic references ( Exp: $x=10; $var = “x”; $$var = “30”; print $x; )
  • It generates an error if you use a variable without declaring it. ( Exp: $a = 10; )
  • It also generates an error if you leave barewords hanging around in the script ( Exp:  foo()  #correct; foo #incorrect; )

use warnings

Generates a warning message based on many criteria, which are described in the POD ‘perllexwarn’. These warnings have nothing to do with strictures, but rather, watch for the most common “gotchas” one is likely to encounter in their programming. It is a best practice to use warnings while writing scripts too. In some cases where the message might be undesirable a certain warning category may be locally disabled within a scope. Additional info is described in ‘warnings’.

Example: Give warning message if uninitialized variable is used in script.

use diagnostics

makes the warnings more verbose, and in a development or learning environment, particularly among newcomers, that’s highly desirable.

Further more errors will be trapped by eval {} and Try::Tiny…

( Exp: $a = 10; )

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