Re^2: why does push not default to $

First of all, that's not true. The following are all acceptable:

push @a;
push @a, 'a';
push @a, 'a', 'b';
[download]

Second, if it was true, that doesn't answer why the second parameter can't be optional, defaulting to $_.

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Re^3: why does push not default to $_? by toolic (Bishop) on Dec 04, 2008 at 21:51 UTC
push @a; It is syntax which will compile, but it does generate a warning. Can you show an example of where this would be used? use strict; use warnings; use diagnostics; use Data::Dumper; my @a = 1..3; push @a; print Dumper(\@a); __END__ % ./728108.pl Useless use of push with no values at ./728108.pl line 9 (#1) (W syntax) You used the push() or unshift() function with no argum +ents apart from the array, like push(@x) or unshift(@foo). That won't usually have any effect on the array, so is completely useless. It +'s possible in principle that push(@tied_array) could have some effec +t if the array is tied to a class which implements a PUSH method. If + so, you can write it as push(@tied_array,()) to avoid this warning. $VAR1 = [ 1, 2, 3 ]; [download]	[reply] [d/l]
Re^4: why does push not default to $_? by LanX (Saint) on Dec 04, 2008 at 21:56 UTC
Toolic, we perfectly know it's not implemented, we meditate WHY it's not implemented! Here a simple usecase: `for (1 .. 100) { next if $_%2; push @even; }` [download] Cheers Rolf UPDATE...PS: Thanx for the interesting link to Builtin functions defaulting to $_	[reply] [d/l]
Re^5: why does push not default to $_? by davidrw (Prior) on Dec 06, 2008 at 01:01 UTC
hmm. i think most people would write that usecase w/`grep` ... `push @even, grep { !($_%2) } 1 .. 100;` [download] (i guess there could be other stuff going on in the loop, but then it's more likely that `$_` would be named..	[reply] [d/l] [select]
Re^6: why does push not default to $_? by LanX (Saint) on Dec 06, 2008 at 01:11 UTC
Re^4: why does push not default to $_? by ikegami (Patriarch) on Dec 04, 2008 at 21:58 UTC
You wouldn't use such a construct. It just showed that your statement wasn't true. So whatever point you were trying to get across was even more lost to me.	[reply]


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Re^2: why does push not default to $_?