noname has asked for the wisdom of the Perl Monks concerning the following question:

Hi Dear Monks,

I have a rather stupid question, lately I had to type a lot of things like that:

$path=$var1.'/'.$var2; and so on,

also I know that the same can be written this way:

$path="${var1}/${var2}";

and it seem that the second way is a bit easier to type (at least for me).

Which one should I stick to ? Are there any benefits/problems with first or second method ?

Thank you!

Replies are listed 'Best First'.
Re: filesystem path concatenation
by Your Mother (Archbishop) on Sep 28, 2015 at 14:35 UTC

    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, $/;

    [download]

    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.)

[reply]
[d/l]

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

      $path = File::Spec->catfile( @directories, $filename );
[reply]
[d/l]

        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

        [download]
[reply]
[d/l]
        I see, thank you all !
[reply]

        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.

Re: filesystem path concatenation
by toolic (Bishop) on Sep 28, 2015 at 14:13 UTC
[reply]
[d/l]
Re: filesystem path concatenation
by karlgoethebier (Abbot) on Sep 28, 2015 at 14:10 UTC

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

    Regards, Karl

    «The Crux of the Biscuit is the Apostrophe»

[reply]
[d/l]

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