perl - Passing array by reference -

i have written simple perl program (driver.pl) passes array reference , calls subroutine add in calculate.pm module.

the calculate.pm module pushes 2 values 100 , 500 array.

when print array in driver.pl file, prints nothing.

driver.pl file:

use calculate; our @my_array; sub init() {     $x = 1;     calculate::add($x, /@my_array); } init(); (@my_array) {     print $_; #prints nothing. } 

---

calculate.pm

sub add() {     ($x, @arr) = @_;     push (@arr, 100);     push (@arr, 200); } 1; 

first of all, here code want:

file calculate.pm:

package calculate;  sub add {   ($x, $arrayref) = @_;   push @$arrayref, 100, 200; }  1; 

file driver.pl:

use calculate;  @array;  sub init {   calculate::add(1, \@array); }  init();  foreach (@array) {   print "$_\n"; } 

what did do? well, fixed (syntax-)errors:

• the reference operator \ nor /.
• loops for or foreach never for each. there each function allows iterate on collections, isn't useful here.
• don't use prototypes (), unless know exactly do, mean, , why have use them here.
• put explicit package declaration library files.

then there severe style issues:

• name packages uppercase names – lowercase names reserved “pragmas”.
• declare variables my, unless need global/dynamic variables. don't.

and newline after print can't hurt.

in our add function, receive array reference. (if know c++: perl references pointers, not c++ references). references scalars, put $arrayref. actual array, dereference @$arrayref – don't copy, or aren't manipulating original.

you slurp remaining arguments array, my ($x, @list) = (1, 2) puts 2 array. in case, 2 array reference! therefore @list contains single element our array reference – isn't same array.

this still isn't elegant code , has architecture problems, should @ least compile.