perl not omnipotent? let's see!

[Moron]

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[Dominus]

Said Moron:

those who agree with the statement could produce a piece of functionality in another language they think cannot be done in perl.

But that's not enough. You said that "(Perl) really is the only language that can do everything any other language can do.". To prove that, you need to prove that no other language can do everything any other language can do. So for each other language l, other than Perl, you need to find something that l cannot do.

That's the part of your statement that I thought was most mistaken, anyway.

[rnahi]

Your claim is pointless. If you are smart and knowledgeable, you may do almost everything in every language.

Somebody even solved The N-queens problem using pure regexes. So Perl could do mostly everything, provided that you know how to. But the real question is "it is really worth doing everything in Perl?

See What is Perl *NOT* good at? for a more reasonable take of this issue.

[tilly]

For a number of years the International Conference on Functional Programming has held an annual competition. In this competition teams are asked in a very short period of time to build a the best piece of software that they can under tight time deadlines. An example was this years task to build a program that would play a variant of cops and robbers.

Any team may use any language.

Most (all?) years, some teams attempt to use Perl for this. As far as I know, Perl has never managed to place in the top 3.

That strongly suggests to me that there are some kinds of tasks which Perl is not ideal for.

[blazar]

For a number of years the International Conference on Functional Programming has held an annual competition. In this competition teams are asked in a very short period of time to build a the best piece of software that they can under tight time deadlines.

A link: ICFP 2005 Contest. To quote from it:
• The judges' prize goes to Dylan Hackers. The judges are happy to proclaim that the Dylan Hackers are an extremely cool bunch of re-hackers.
• First prize goes to KiebererAndXiaoTou. The judges are happy to proclaim that Haskell is the programming tool of choice for discriminating hackers.
• Second prize goes to Dylan Hackers. The judges are happy to proclaim that Dylan is a fine programming tool for many applications.
• Third prize goes to Combat-Tanteidan. The judges are happy to proclaim that Haskell is also not too shabby.

Seems like O'Caml, winner for many years of 1st/2nd/3rd prize is now nothing but a distant memory. (Thanks, g.!!)

[GrandFather]

If it is computable then any Turing complete language can compute it. Ook! is Turing Complete (appart from issues of memory size) and I can write an Ook! interpreter in Perl thus Perl (by using the Ook! interpreter) can compute anything computable.

[spiritway]

If it is computable then any Turing complete language can compute it.

++ to you, GrandFather - when all is said and done, they can all do essentially the same thing. The choice is a matter of practical considerations.

[itub]

Sorry, I'm too lazy to provide code samples.

The question is ambiguous. Of course, everything you can do in Perl, you can do in C, because perl is implemented in C. And everything you can do in C, you can do in assembler.

The real question, IMO, is whether you can express things in a "natural" and efficient way in a language. I think any declarative language such as Prolog or SQL is full of examples of things that are trivial to do in those languages, but awkward and inefficient in Perl. Of course, you can use SQL and Prolog from Perl if you want...

Another case is when you need speed and memory efficiency. Can you multiply large matrices in Perl efficiently? Not really, unless you use PDL or some other numeric extension, which happens to be implemented in C (there might be some in Fortran as well).

[tirwhan]

OK, please try to do this in perl.

[Tanktalus]

I can't even do that in C, how the heck would I be able to do that in perl? :-)

[apotheon]

You are E-ville. I like it.

[Moron]

Aw come on it's a simple one liner, surely... ;)

perl -e 'system $_ while(<>);'

[steelrose]

The question shouldn't be 'CAN it be done in Perl' but 'how EFFICIENT is the Perl solution'.

That, as most of you are aware, becomes the dreaded 'How good is/are your benchmark test(s)?' scenario.

So, that being said, there will never be a solution that will fit everyone's criteria. Those that believe in the power of perl will continue to do so, and those that do not, will not... IMO of course.

[Perl Mouse]

This thing could go either way (but I disagree with your claim both ways).

Either you mean Perl is the only language that has all constructs/techniques that any other language has. That isn't true - for instance, Perl doesn't have continuations or co-routines. Or even POSIX regular expressions (always prefer to find the longest match instead of the first match).

Or you mean that Perl is the only language that can simulate or mimic constructs/techniques that any other language has. That isn't true either, because if it can be simulated in Perl, in can in C, as C is driving perl.

[Skeeve]

If we limit ourselves to algorithms, Perl Mouse is right with her/his statement.

If I recall my computatenol lectures correct, it's a prooven fact that a turing machine can compute any algorithm. So it's a fact that for any algorithm you can express in any computer language, there is a turing machine that is an implemantation for this algorithm.

If that statement is correct, and please correct me everyone who knows better, it's a fact that a perl program can compute any algorithm. It's simply a matter of implementing a turing machine in perl.

Agreed: It's very theoreticaly ;-)

[xdg]

It's a fine challenge. Of course, given the original claim, it's important to recognize that these are not equivalent (replacing "Perl" with "A" to make the point):

A is the only language that can do everything any other language can d
+o.

Everything that can be done in another language can be done in A.

[TedPride]

Data structures tend to take up a lot more space in Perl than they do in C++. Therefore, given a large structure and limited memory, a program could work in C++ but not in Perl.

[Anonymous Monk]

I have to admit it. Excellent choice of nick.

As for the rest, try doing your advocacy at comp.lang.c. Perhaps you would get more challenging answers.