In fact you seem to be calculating all of the odd numbers rather than the prime numbers.

Indeed, and in a very clumsy way, including the deprecated use of a map in void context...

Update: at the moment of this update this node has gained a reputation of -4. So far so fine. However this should imply that at least four persons did disagree with my claim. I must deduce that those persons think that

@prime = (1,2);
map { push(@prime,$_) if (($_ % 2) != 0) } (2 .. 100);
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my @prime=(1,2,grep $_%2, 2..100);
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PS: from perldoc perlstyle:

Avoid using grep() (or map()) or `backticks` in a void context, that is, when you just throw away their return values. Those functions all have return values, so use them. Otherwise use a foreach() loop or the system() function instead.

including the deprecated use of a map in void context

Is map in a void context deprecated?

I thought that the main concern with using map in a void context was the inefficiency of building a results list that is then discarded--but that was corrected in 5.8.1 (from the delta):

map in void context is no longer expensive. map is now context aware, and will not construct a list if called in void context.

---

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.

Lingua non convalesco, consenesco et abolesco. -- Rule 1 has a caveat! -- Who broke the cabal?

"Science is about questioning the status quo. Questioning authority".

In the absence of evidence, opinion is indistinguishable from prejudice.

Whilst I agree that deprecated is too strong a word and that it is no longer wasteful to use it in this way, it does seem semantically odd to use map in a void context, which I think has always been one of the major objections to doing this, something like:

do { push(@prime,$_) if ($_ % 2) } for (2 .. 100);
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is probably closer to being clear (for me at any rate.)

/J\