in reply to Re^11: eof not recognised when applying diamond operator to invocation arguments?
in thread eof not recognised when applying diamond operator to invocation arguments?

Good grief!! Even the Perl documentation makes the distinction between the two:

I didn't say what you do makes no sense; I said the reason you gave makes no sense. It doesn't mean there are no other reasons that do make sense.

but the documentation starts off by using "for" to describe the C-style form of "(;;)

C-style loops are almost always used as for loops, so that's pretty accurate (although they are really just while loops.)

and "foreach" to describe the Perl-style form of "$var (list)".

Actually, the documentation isn't as clear as your purport it to be. It appears that section was written to describe that syntax, but it says "The foreach loop iterates over a normal list value and sets the variable VAR to be each element of the list in turn." for VAR (EXPR..EXPR) doesn't match that definition.

The Perl documentation is one of those that seem to forget about Perl-style for loops.

So I'm perfectly in line with how the Perl documentation describes them.

But I'm asking about that case that's not documented! So we've looped back to here.

My point about discouraging "for" loops was if the two were actually two distinct looping styles

If the two were actually two distinct looping styles, ...? Part of that sentence seems to be missing.

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Re^13: eof not recognised when applying diamond operator to invocation arguments?
by Argel (Prior) on Jan 17, 2011 at 23:42 UTC
    Good point about the syntax, though the end result is the same -- "for" and "foreach" are given separate treatment.

    Regarding Perl style "for" loops, I think in general, if I was using the "(;;)" format then I would use "for" and if I was using the "$var (list)" format I would use foreach. But there could be exceptions and I'm not sure how to articulate it any better than in my first attempt. (^_^;) :-/

    Regarding the missing text, this is what I wrote:

    My point about discouraging "for" loops was if the two were actually two distinct looping styles (i.e. that "foreach" was not a synonym for "for", so that "for" could only be used for C-style for loops). Sorry if there was any confusion over that.
    If you see all of that then what I meant was "my comment above about discouraging the use of 'for' loops was predicated on restricting "for" loops to only the C-style (;;) syntax".

    Elda Taluta; Sarks Sark; Ark Arks
[reply]

      My question is still unanswered. I'm trying to determine which of the following you would use and why: 

      for (1..5) { say; }
foreach (1..5) { say; }

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      I've been specifically asking how the two argument form fits in, yet you keep answering with statements that only cover the three argument form and the list argument form.

[reply]
[d/l]
        The optimization which makes for (1..5) {...} special is supposed to be invisible to Perl programmers. (Other than the reduced memory usage...) So if someone formatted the list form differently than the three argument form, I would expect them to format that in the list form, which is what it acts like.
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