I tried a prove of concept of overiding push, such that a missing second parameter defaults to $_. 
use subs 'push';

my @a;
$_="x";

# push @a;  # Error: "Can't use an undefined value as an ARRAY referen
+ce ..."
print @a;

# Override!
sub push (\@_;@) {
  CORE::push( @{+shift},@_) ;
}

push @a;
print @a; # prints "x"

@b=("y","z");
push @a,@b;
print @a; # prints "2"

[download]
So it's possible to use push defaulting to $_, but a second Array to push will be forced into scalar context! 8(

So the prototypesymbol _ doesn't work with parameterlists ...

Cheers Rolf

In reply to Re^5: why does push not default to $_? (simple) by LanX
in thread why does push not default to $_? by LanX

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