#! /usr/bin/perl -wT
 
#
# PERL module/script to decide to which array an element belongs to
# when there are multiple arrays.
# Assumes that the arrays contain UNIQUE element names
# Element_Array_Map() takes in elementName as input and returns the name of array it's in.
# 
 
#
# sub Element_Array_Map() BEGINS
 
sub Element_Array_Map($) {
 
#
# Requested elementName
 
  local ($element) = $_[0];
 
#
# Uncomment the following line for debugging purposes
# print("Requested element is $element\n");
 
#
# A hash of arrays
# Each array contains several element names
# Each array can have different number of elements 
# Elements of each array are UNIQUE
# Hash definition can be modified to include 'N' arrays
 
  my %HASH_OF_ARRAYS = (
      ARRAY1 => ['Element1', 'Element2'], 
      ARRAY2 => ['Element3', 'Element4', 'Element5', 'Element6'],
      ARRAY3 => ['Element7', 'Element8', 'Element9'],
      ARRAY4 => ['Element0'],
      );
 
#
# Search the hash of arrays to find out to which array does the 
# requested element belong
 
  foreach my $element_array (keys %HASH_OF_ARRAYS) {
    foreach (@{$HASH_OF_ARRAYS{$element_array}}) {
      if ( $element =~ m/$_/ ) {  
        print "$element is in $element_array\n";
        return $element_array;
      }
    }
  }
 
} 
# sub Element_Array_Map() ENDS
 
#
# Call it after the function to avoid the following error
# 'main::Element_Array_Map() called too early to check prototype'
# If not using '-wT' flags, this function can be called before its 
# definition. The value '$element_array' can be passed on to other 
# modules/scripts, if necessary.
 
my $elementName   = "Element1";
my $element_array = Element_Array_Map($elementName);
 
# Uncomment the following line for debugging purposes
# print "$element_array\n";