Re^2: RFC: Tutorial: use strict; now what!?

[JavaFan]

beginners who use soft references should be using hashes instead,

Hashes can be the solution. However, in almost all cases a hash based solution is done is such away it has all the disadvantages of not using strict, and none of the advantages.

Writing $hash{key} isn't any better than no strict; $key. In fact, it's worse. If you don't have strict enabled, and you typo and write $kye (once), you still get a compile time warning (assuming they are enabled). If you typo $hash{kye}, at best you get a runtime warning of an uninitialized value, depending on how it's used. But you may get no warning or error, regardless whether you have strict or warnings enabled.

Only if you would write:

    my $KEY = "...";
    ...
    $hash{$KEY};

you get protected against typos, but I very seldomly see people using hashes that way. But then you still don't get all the benefits of using regular, lexically scoped, variables:

    my $KEY1 = "something";
    ...
    my $KEY2 = "something";
    ...
    $hash{$KEY1} = "...";
    $hash{$KEY2} = "...";   #  Ooops.

Perl will warn you if you declare a variable with the same name in the same scope. A benefit you lose if you implement variables as hash keys.

For me, code that uses hashes as if the entries were variables is a red flag. It indicates the most dangerous type of programmer. It's someone who thinks he's past the grasshopper stage, but really isn't yet.

Hashes as a bag of variables should be treated as Fugu. Only after 25 years of training, the first 14 of which all you do is cook rice 16h/day, 365 days/year are you allowed to look at the fish, and it takes another 25 years to master the slicing. Aka, it's only the experts, and they usually won't do it. It's certainly not for beginners.

I rather see someone using a soft reference, than a hash as a bag of variables. That cure is worse than the disease.