Re: Perl 5.10: switch statement demo

[LighthouseJ]

I don't know why people want a verbatim 'switch' statement when you can use a for-statement.

#!/usr/bin/perl -w
use strict;
{
    for (1..40) {
    print;
    ($_ % 3 == 0) && print q! fizz!;
    ($_ % 5 == 0) && print q! buzz!;
    ($_ % 7 == 0) && print q! sausage!;
    print "\n";
    }
}

I generally use a for loop in conjunction with regular expression matches, like this trivial example:

#!/usr/bin/perl -w
use strict;
{
    my @items = qw/The three principal virtues of a programmer are Laz
+iness, Impatience, and Hubris. See the Camel Book for why/;
    for (@items) {
    /^[A-Z]/ && do {
        print "Found a proper noun?  $_\n";
        next;
    };

    /[,.]/ && do {
        print "This word has punctuation:  $_\n";
        next;
    };

    print "This word seems uninteresting:  $_\n";
    }
}

It has a lot of flexibility where you can mix and match parts and get real nice uses out of it. I've always used it fully and got very good results --without waiting for a proper switch statement.

[robin]

You can use when in a for loop:

for (@items) {
    when (/^[A-Z]/) {
        say "Found a proper noun?  $_";
    }

    when (/[,.]/) {
        say "This word has punctuation:  $_";
    }

    say "This word seems uninteresting:  $_";
}

[LighthouseJ]

I guess that's kind of my point. The really useful and powerful things in todays computing industry like Perl, UNIX, even RISC processors all merely provide you with a basic set of tools and rely on you (the user) to put the simple tools together to make a useful mechanism.

Stuff like adding a named "switch" statement or needing a "when" keyword just complicates it unnecessarily IMO.

I had a discussion about this with an Oracle DBA. Needless to say we maintained our differences of opinion.

[robin]

Well, I wasn't really trying to make a polemical point. You just gave me a convenient excuse to draw attention to a feature of the switch implementation that I thought people might be interested in hearing about. :-)

Needless to say, though, I don't agree with you. If I did, then I wouldn't have implemented the switch feature, presumably! It sounds odd to me to hear Perl described as a "simple tool". What I like about it is precisely the opposite: the fact that it's rich and interesting, and usually has More Than One Way To Do It.

Java is a simple language, but it's difficult to write a useful Java program that is simple. Perl is not a simple language, but it is a language in which it's possible to write simple programs.