Re^5: Problem with traversing a two dimensional array (to create an arrayref use [ ] )

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Re^6: Problem with traversing a two dimensional array (to create an arrayref use [ ] ) by Laurent_R (Canon) on Jan 16, 2014 at 19:05 UTC
Yeah, I know the differences between a list and an array. And I know that split returns a list, but it is slightly more tricky than that. If you do this: `my $c = qw / 4 6 8 90/;` [download] $c's value becomes the last element of the list (90). But if you do this: `$c = split / /, "the quick brown fox";` [download] $c is now 4, the number of elements of the array (I think this would also trigger a warning that @_ may be overwritten). But if you do this: `$c = (split / /, "the quick brown fox")[2];` [download] now this behaves as an anonymous array et $c is assigned to "brown" (and there no longer any warning, because Perl sort of built an anonymous array). And if you do this: `$c = [split / /, "the quick brown fox"];` [download] $c's value is now something like "ARRAY(0x80359d10)", i.e. an array reference. and you need something like this: `print $c->[2];` [download] to print the third element of the array. This is really an array ref, not an array.	[reply] [d/l] [select]
Re^7: Problem with traversing a two dimensional array (to create an arrayref use [ ] ) by Anonymous Monk on Jan 16, 2014 at 19:50 UTC
Your terminology is a bit off. The construction `(split...)[2]` picks out one element of the list returned by `split` (it does not create an anonymous array). OTOH, `[split...]` creates an anonymous array (initialized by the list returned by `split`) and returns a reference to it. Saying `[split...]->[2]` would create an anonymous array, then return one element of it (and then discard the anonymous array).	[reply]
Re^8: Problem with traversing a two dimensional array (to create an arrayref use [ ] ) by Laurent_R (Canon) on Jan 16, 2014 at 23:19 UTC
Oh, well, my terminology might be off and, although I think that I can claim to have a relatively good command of the English language, it is not my mother tongue and I may sometimes goof on some fine subtleties, but I was careful enough not to say that `(split...)` creates an anonymous array, but only that the thing does behave (at least in a number of respects) as if it were an anonymous array. Accessing elements with an index, manufacturing array slices, getting an element count in a scalar context, just to give a few examples, are things that you can do with an array and not with a list. But, OK, I have no desire to argue endlessly on this (especially not with an Anonymous Monk, where I don't even know if the person talking to me is always the same person), let's consider that you were right and forget it. I have no intention to argue any further on this.	[reply] [d/l]
Re^9: Problem with traversing a two dimensional array (to create an arrayref use [ ] ) by no_slogan (Deacon) on Jan 17, 2014 at 00:13 UTC


Think about Loose Coupling
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