What toolic said but you're better off in general, I argue, reaching for a module like Path::Tiny.

use strictures;
use Path::Tiny;
my $root = "some/place";
my $name = "somefile.ook";
my $path = path( $root, $name );
print $path, $/;
print $path->relative("some"), $/;
print $path->absolute, $/;
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There are many advantages to this style especially in code that will grow; reading, writing, iterating, relative, absolute... all kinds of fun made simple and easy for others to follow when they read your code. (update: added a missing comma.)

Or even File::Spec which is a core module :-

$path = File::Spec->catfile( @directories, $filename );

I prefer the higher level of abstraction with the same accurate portability by far :P

moo@cow~>perldoc -m Path::Tiny | ack File::Spec
use File::Spec 3.40 ();
    my $cpath = $path = File::Spec->canonpath($path);
#pod Gives you C<< File::Spec->rootdir >> as a C<Path::Tiny> object if
+ you're too
sub rootdir { path( File::Spec->rootdir ) }
    @{$self}[ VOL, DIR, FILE ] = File::Spec->splitpath( $self->[PATH] 
+);
#pod in L<File::Spec> would normally do so on your platform.  If you n
+eed them
#pod like C<catfile> or C<catdir> from File::Spec, but without caring 
+about
#pod C<< File::Spec->splitpath( $path->stringify ) >> or C<"."> for a 
+path without a
#pod parent directory portion.  Because L<File::Spec> is inconsistent,
+ the result
#pod C<< File::Spec->abs2rel() >>.
# Easy to get wrong, so wash it through File::Spec (sigh)
sub relative { path( File::Spec->abs2rel( $_[0]->[PATH], $_[1] ) ) }
#pod equivalent to what L<File::Spec> would give from C<splitpath> and
+ thus
friendlier to use than L<File::Spec> and provides easy access to funct
+ions from
Gives you C<< File::Spec->rootdir >> as a C<Path::Tiny> object if you'
+re too
in L<File::Spec> would normally do so on your platform.  If you need t
+hem
like C<catfile> or C<catdir> from File::Spec, but without caring about
C<< File::Spec->splitpath( $path->stringify ) >> or C<"."> for a path 
+without a
parent directory portion.  Because L<File::Spec> is inconsistent, the 
+result
C<< File::Spec->abs2rel() >>.
equivalent to what L<File::Spec> would give from C<splitpath> and thus
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I see, thank you all !

File::Spec is definitely The Right Way™ to do this, because it is both purposeful and portable.   You really don’t want to have to be mucking-around with slashes, do you?   Worrying whether they ought to be forward or backward on this system or that?   Naww-w-w-ww, not if someone else has already done it for you!   And, since it is in the Core, you don’t have to install it:   it is already there.

$path="$var1/$var2";
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Another idea: let it write ;-) perl -E 'say join "/", qw (foo bar);'

Regards, Karl