truthseeker66:

The dot operator combines two strings. So given:

my $t = "apple";
my $u = "banana";

my $x = "Combined: " . $t . $u . "\n";
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Perl starts to combine the strings:<\p>

my $x = "Combined: " . $t . $u . "\n";            # before we start
      = "Combined: " . "apple" . "banana" . "\n"; # expanded variables
      = "Combined: apple"      . "banana" . "\n"; # combined first two
      = "Combined: applebanana"           . "\n"; # then the next
      = "Combined: applebanana\n";                # then the last
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...roboticus

When your only tool is a hammer, all problems look like your thumb.

First off fellow monk understand just what you are doing here.

Those dots you are referring to are the string concatenation operator. Each operator has a left hand side and a right hand side. I won't even start getting into precedence here since it reall y doesn't matter all that much.

my $thing = "Coca" . "Cola";
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As far as the variables them selves consider this code block:

my ($left,$right)=@_;
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my $left=$_[0];
my $right=$_[1];
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my $left = shift @_;
my $right = shift @_;
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#
# NEVER ASSUME!!!
my $right = pop @_;
my $left = pop @_;
#
# You may not get the result you are after!!
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Clear as mud?

Thank you

my $left=$_[0];
my $right=$_[1];
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which is the same as

my $left = shift @_;
my $right = shift @_;
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It is not the same at all. The first version doesn't modify @_. The second one does modify it. The difference is often very important. (For example, if you're planning on using goto.)

use Test::More;
use Data::Dumper;

sub func1 {
    my $left=$_[0];
    my $right=$_[1];
    goto \&Data::Dumper::Dumper;
}

sub func2 {
    my $left = shift @_;
    my $right = shift @_;
    goto \&Data::Dumper::Dumper;
}

my @args = qw( a b );

# Are they the same??
is(
    func1(@args),
    func2(@args),
    "they're the same!",
);

done_testing();
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perl -E'sub Monkey::do{say$_,for@_,do{($monkey=[caller(0)]->[3])=~s{::}{ }and$monkey}}"Monkey say"->Monkey::do'

The difference is often very important.

And the difference often doesn't matter at all. As in the OP's example. In which case they are essentially the same. Similar. Whatever. Yes, I know what the difference is; I often pass @_ to other methods after shifting off the object. And often I don't.

Regarding question# 2 i believe now you do understand about dot(.); so first dot(.) is to concatenate left side variable. and right side dot(.) is to concatenate right of that variable. If string or variable is not available then it will simply ignore.

No. "If a string or variable is not available" then it is an empty string or undef and an empty string will be concatenated (not simply ignored).