On Sun, Sep 29, 2002 at 09:31:46PM -, Smylers wrote:
Consider this Perl 5:
while ()
{
# ...
foreach my $fruit (qwapple banana cherry)
{
# ...
}
}
Inside the inner loop C$_ still holds the current line. In the
equivalent Perl 6 syntax, insider the
Paul Johnson wrote:
On Sat, Sep 21, 2002 at 10:05:50AM -, Smylers wrote:
Many Perl programs use C$_ to mean
'the current line'. 'A2' gives the Perl 6 syntax for this as:
while $STDIN {
Maybe somewhere in the middle of
it, it's necessary to have a Cfor loop iterating
Larry Wall wrote:
On 20 Sep 2002, Aaron Sherman wrote:
: Does that mean that I can't
:
: for $x - $_ {
: for $y - $z {
: print $_, $z\n;
: }
: }
:
: And expect to get different values?
That's correct. Name the outer
On Sat, Sep 21, 2002 at 10:05:50AM -, Smylers wrote:
Larry Wall wrote:
On 20 Sep 2002, Aaron Sherman wrote:
: Does that mean that I can't
:
: for $x - $_ {
: for $y - $z {
: print $_, $z\n;
: }
: }
:
: And
On 21 Sep 2002, Smylers wrote:
Larry Wall wrote:
On 20 Sep 2002, Aaron Sherman wrote:
: Does that mean that I can't
:
: for $x - $_ {
: for $y - $z {
: print $_, $z\n;
: }
: }
:
: And expect to get different
On Thu, 19 Sep 2002, Brent Dax wrote:
: Aaron Sherman:
: # topicalize: To default to C$_ in a prototype (thus
: # acquiring the caller's current topic).
:
: Well, to topicalize a region of code is actually to specify a different
: topic, that is, a different value for $_. For example:
:
:
Larry Wall:
# That binds the dynamically surrounding $_ to $x as an
# out-of-band parameter. Can also bind to $_ to make it the
# current topic.
The problem I have with that is this:
sub for_trace(*@array, block) {
loop($_=0; $_ @array; $_++) {
On Fri, 2002-09-20 at 10:36, Larry Wall wrote:
On Thu, 19 Sep 2002, Brent Dax wrote:
: (An aside: it strikes me that you could use Cgiven as a scoped lexical
: alias, i.e.
: given $bar - $foo {
: print $foo;
: }
Sure, though it also aliases to $_.
Does that mean
On Fri, 20 Sep 2002, Brent Dax wrote:
: Larry Wall:
: # That binds the dynamically surrounding $_ to $x as an
: # out-of-band parameter. Can also bind to $_ to make it the
: # current topic.
:
: The problem I have with that is this:
:
: sub for_trace(*@array, block) {
:
On 20 Sep 2002, Aaron Sherman wrote:
: On Fri, 2002-09-20 at 10:36, Larry Wall wrote:
: On Thu, 19 Sep 2002, Brent Dax wrote:
:
: : (An aside: it strikes me that you could use Cgiven as a scoped lexical
: : alias, i.e.
: : given $bar - $foo {
: : print $foo;
: : }
:
: Sure,
On 20 Sep 2002, Aaron Sherman wrote:
: I assumed that's what C//=$_ was. It does have the disadvantage of
: looking like variable assignment, though.
BTW, latest leaning is toward = rather than //= for parameter defaults,
since it can, in fact, be undef if the parameter is supplied, while //=
On Fri, 20 Sep 2002, Larry Wall wrote:
The current thinking as of Zurich is that the given passes in
separate from the ordinary parameters:
sub ($a,$b,$c) is given($x) {...}
That binds the dynamically surrounding $_ to $x as an out-of-band
parameter. Can also bind to $_ to make it the
Larry said:
BTW, latest leaning is toward = rather than //= for parameter
defaults, ...
Horray!
Sorry. Couldn't resist. :-)
-angel
Simple men are happy with simple presents
On Fri, 20 Sep 2002, Sean O'Rourke wrote:
: On Fri, 20 Sep 2002, Larry Wall wrote:
: The current thinking as of Zurich is that the given passes in
: separate from the ordinary parameters:
:
: sub ($a,$b,$c) is given($x) {...}
:
: That binds the dynamically surrounding $_ to $x as an
Personally, I like the looks of
sub foo($a, $b is given) { ... }
Does this mean that we allow/encourage uses of $_ other than as a default
for an optional argument? I think it would be less confusing and
error-prone to associate the underscore-aliasing with the parameter $_
will
On Sat, 2002-09-14 at 04:16, Luke Palmer wrote:
When a bare closure is defined, it behaves the same as a signatureless
sub. That is, it topicalizes the first argument, and hands them all over
in @_. So your topic passing is just, well, passing the topic, like
any ol' argument.
Ok,
Aaron Sherman:
# topicalize: To default to C$_ in a prototype (thus
# acquiring the caller's current topic).
Well, to topicalize a region of code is actually to specify a different
topic, that is, a different value for $_. For example:
$foo = new X;
$bar = new Y;
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