Re^5: Array/List Strangeness

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Re^6: Array/List Strangeness by LanX (Saint) on Aug 05, 2009 at 11:12 UTC
That's what Taulmarill meant. Basically: an "empty" `array` can have any size, but an empty `list` always has size 0. UPDATE: that should show it... `DB<1> @a[3..5]=() DB<2> @b[3..5]=() DB<3> print scalar @a 6 DB<4> print ( () = @a,@b ) DB<5> @c= @a,@b DB<6> print scalar @c 6 DB<7> @c=(@a,@b) DB<8> print scalar @c 12 DB<9> print ( () = (@a,@b) ) DB<10> push @a,@b DB<11> print scalar @a 12 DB<12> x @a 0 undef 1 undef 2 undef 3 undef 4 undef 5 undef 6 undef 7 undef 8 undef 9 undef 10 undef 11 undef` [download] Line 12 clearly shows, that concatenating two "empty" arrays leads to a larger "empty" array... Anyway the difference between line 5 and 7 is somehow surprising ... UPDATE: Aaaaaargh!!! 8) In line 5, I fell into the scalar comma operator trap again ... it's basically `(@c=@a),(@b)` Cheers Rolf	[reply] [d/l] [select]
Re^7: Array/List Strangeness by jethro (Monsignor) on Aug 05, 2009 at 13:06 UTC
Well, Taulmarill was questioning Ikegamis words 'non-existing array element'. So I'm just pointing out that there is a real difference between non-existing array element and undef'd array element (even if we would wish otherwise to have more consistency). ++ for what you are saying after 'Basically:', an excellent description of the situation	[reply]
Re^8: Array/List Strangeness by Taulmarill (Deacon) on Aug 05, 2009 at 13:29 UTC
I admit that i might have misunderstood something here .... although i'm not sure what.... Could we from now on agree not to talk about (non)existing array elements, but about elements <= $#array and elements > $#array. That might make things easier for my twisted, sleep deprived mind. update: also i'd like $[ to stay 0.	[reply]
Re^9: Array/List Strangeness by LanX (Saint) on Aug 05, 2009 at 16:28 UTC
Re^8: Array/List Strangeness by LanX (Saint) on Aug 05, 2009 at 16:36 UTC
++ for what you are saying after 'Basically:', an excellent description of the situation Actually it should be defined what "empty" means. `undef` can be an existing element of a list! `DB<1> p scalar ( ()=(undef,undef) ) 2` [download] Cheers Rolf	[reply] [d/l] [select]