Re: Is there a way to bulky feed?
I understand now. Given a large list, you'd like to assign chunks of
the list to an array, easily, while looping. In other words, you're
looking for a way to abbreviate this:
my $chunk_size=10_000;
my @big=''..'mnop';
for ^...@big :by $chunk_size {
my @chu...@big[$_..($_+$chunk_size,@big.end).min]
... # Do stuff with @chunk
}
I'm a perl6 novice so there probably is a more elegant way to write
the above already.
>From your original email, I like this idea-
for ''..'mnop' -> *...@chunk[10_000] { ... } # @chunk is 1 elems or less
though I think the syntax has to change a bit. I used the "*@" sigil
because "chunk" is slurpy, but only up to 10,000 items. Wrong on a
couple levels?
By the way, you shouldn't predeclare "@chunk" as you did in the
original example-
my @a = <1 2 3 4>; my @b[2]; for @a ->@b {;}
the @b in the pointy block is a new declaration that shadows the
earlier "my @b[2]" declaration.
Re: Is there a way to bulky feed?
On Fri, Jul 10, 2009 at 12:29 AM, yary wrote:
>
>
> On Wed, Jul 8, 2009 at 8:45 PM, Xiao Yafeng wrote:
>
>> Any thoughts?
>>
>
> First let's fix the whitespace in your post so it's easier to read-
>
> My question is: could I write below code in perl6:
>
> # 2 loops like for @a -> $b[0],$b[1] {;}
> my @a = <1 2 3 4>; my @b[2]; for @a ->@b {;}
>
> my @a = <1 2 3 4>; my @b; for @a -> @b{;}# 1 loop
>
> # 2 loops like grep {$^a+$^b >3} <== @a;
> my @a = <1 2 3 4>; my @b[2];
> grep(@b){say 'yes' if +...@b>3} <== @a;
>
> # slurp
> my @a = <1 2 3 4>; grep{say 'yes' if +...@_>=10} <== @a;
>
> One style point, generally a list of numbers is written as
> my @a = 1..4; # list of numbers, <1 2 3 4> is a list of strings
> my @a = '1'..'4' # equivalent to <1 2 3 4>
>
> As for your original question, I am not quite sure what you're asking. Do
> you want a simpler way to write
> for 一..四 {say "$^x $^y";}
> 一 二
> 三 四
> (... which assumes that unicode sequencing is working, I can't test that on
> my machine!)
>
> Or do you want something like-
> for -> $a {for ->$b {say "$a $b"}}
>
> Or using more memory and less looping (at least superficially!)
> for 'a'..'d' X {say "$^p $^q"};
>
> In other words, if you can write some code that runs and tell us how you'd
> like to simplify it, I might be able to answer better.
>
What I thought is reducing loop times.
In some case, we don't need pop a item from a list one by one. Acoording to
memory capacity of machine, we can get more than one items from the list.
for a simple example,
for 1..100 -> $x {
func1($x) if $pid = fork;
}
above code will loop 100 times, fork 100
processes and waste most of memory on machine.
if I can say,
my @b[1]; for 1..100 -> @b{
func2(@b) if $pid = fork;
}
IMHO, preceding code will be better in term of memory
utilization.
Re: Is there a way to bulky feed?
On Wed, Jul 8, 2009 at 8:45 PM, Xiao Yafeng wrote:
> Any thoughts?
>
First let's fix the whitespace in your post so it's easier to read-
My question is: could I write below code in perl6:
# 2 loops like for @a -> $b[0],$b[1] {;}
my @a = <1 2 3 4>; my @b[2]; for @a ->@b {;}
my @a = <1 2 3 4>; my @b; for @a -> @b{;}# 1 loop
# 2 loops like grep {$^a+$^b >3} <== @a;
my @a = <1 2 3 4>; my @b[2];
grep(@b){say 'yes' if +...@b>3} <== @a;
# slurp
my @a = <1 2 3 4>; grep{say 'yes' if +...@_>=10} <== @a;
One style point, generally a list of numbers is written as
my @a = 1..4; # list of numbers, <1 2 3 4> is a list of strings
my @a = '1'..'4' # equivalent to <1 2 3 4>
As for your original question, I am not quite sure what you're asking. Do
you want a simpler way to write
for 一..四 {say "$^x $^y";}
一 二
三 四
(... which assumes that unicode sequencing is working, I can't test that on
my machine!)
Or do you want something like-
for -> $a {for ->$b {say "$a $b"}}
Or using more memory and less looping (at least superficially!)
for 'a'..'d' X {say "$^p $^q"};
In other words, if you can write some code that runs and tell us how you'd
like to simplify it, I might be able to answer better.
Is there a way to bulky feed?
My question is: could I write below code in perl6:
my @a = <1 2 3 4>; my @b[2]; for @a ->
@b {;} # 2 loops like for @a -> $b[0],$b[1]{;}
my @a = <1 2 3 4>; my @b; for @a -> @b
{;} # 1 loop
my @a = <1 2 3 4>; my @b[2];
grep(@b){say 'yes' if +...@b>3} <== @a; # 2 loops like
grep {$^a+$^b >3} <== @a;
my @a = <1 2 3 4>; grep{say 'yes' if +...@_
>=10} <== @a; # slurp
Since memory is cheaper and cheaper, bulky feed can maximize to make use of
memory and reduce loops.
Any thoughts?
