In Perl, the subroutine uses a list of variable length parameters, so the number of parameters is no longer restricted, reflecting the advantages of dynamic language. Since the passed is a reference, it can be changed in the SUB.
SAMLE01.PL
#! / usr / bin / perl
Sub sub_routine {
$ _ [0] = "Hello"; $ _ [1] = 999;
Print "SUB_PAR1: $ _ [0] / N";
Print "SUB_PAR2: $ _ [1] / N";
}
MY $ PAR1 = "Abcde";
MY $ PAR2 = 2;
Print "Main_par1: $ PAR1 / N";
Print "Main_PAR2: $ PAR2 / N";
& Sub_Routine ($ PAR1, $ PAR2);
Print "Main_par1: $ PAR1 / N";
Print "Main_PAR2: $ PAR2 / N";
operation result:
Main_par1: abcde
Main_par2: 2
SUB_PAR1: Hello
Sub_par2: 999
Main_par1: Hello
Main_par2: 999
If you do not want to change the value of the parameters in the subroutine, you can use a method of local variables.
Sample02.pl
#! / usr / bin / perl
Sub sub_routine {
MY $ PAR1 = $ _ [0];
MY $ PAR2 = $ _ [1];
$ PAR1. = "fghijklmn";
$ PAR2 = 10000;
Print "SUB_PAR1: $ PAR1 / N";
Print "SUB_PAR2: $ PAR2 / N";
}
MY $ PAR1 = "Abcde";
MY $ PAR2 = 2;
Print "Main_par1: $ PAR1 / N";
Print "Main_PAR2: $ PAR2 / N";
& Sub_Routine ($ PAR1, $ PAR2);
Print "Main_par1: $ PAR1 / N";
Print "Main_PAR2: $ PAR2 / N";
operation result:
Main_par1: abcde
Main_par2: 2
Sub_par1: Abcdefghijklmn
SUB_PAR2: 10002
Main_par1: abcde
Main_par2: 2
