Hello demichi,

I agree with LanX, readability is the key here. Consider the following, which all print MyTextWilmaishere.:

#! perl
use strict;
use warnings;

my $ref_HoH =
{
    Fred   => { wife => 'Wilma', daughter => 'Pebbles',   },
    Barney => { wife => 'Betty', son      => 'Bamm-Bamm', },
};

my $var = 'Fred';
my $key = 'wife';

print  "MyText$ref_HoH->{$var}{$key}ishere.\n";             # interpol
+ated
print  "MyText$$ref_HoH{$var}{$key}ishere.\n";              # interpol
+ated
print  "MyText" . $ref_HoH->{$var}{$key} . "ishere.\n";     # concaten
+ated
print  "MyText" . $$ref_HoH{$var}{$key} . "ishere.\n";      # concaten
+ated
printf "MyText%sishere.\n", $ref_HoH->{$var}{$key};         # template
+d
printf "MyText%sishere.\n", $$ref_HoH{$var}{$key};          # template
+d
[download]

My preference is for printf, which presents the complete structure of the output up-front, in the format string; but concatenation is always a valid option; and either option is clearer, and therefore more maintainable, than the equivalent interpolation.

Hope that helps,