Introduction to $a and $b in Perl _perl

Even if the strict and warnings options are turned on, the following code does not have errors and warnings.

Copy Code code as follows:

#!/usr/bin/perl
Use strict;
Use warnings;
Sub Test {
$a = 1;
$b = 2;
Print $a, "\ n";
Print $b, "\ n";
}
Test ();
1;

The following is an explanation of these two variables in the Perl documentation:

Perldoc Perlvar
$a
$b Special Package variables when using sort (), the "sort" in Perlfunc.
Because of this specialness $a and $b don ' t need to is declared (using use VARs, or we ()) even when using the ' strict ' VA  Rs ' "pragma. Don ' t lexicalize them with "My $a" or "I $b" if you want to is able to use them in the sort () comparison block or Functio N.