在Perl 6中需要简单的并行性示例

Question

我正在尝试同时学习Perl 6和并行/并发.

对于一个简单的学习练习,我有一个550'.htm'文件的文件夹,我想要所有这些文件中的代码行总和.到目前为止,我有这个:

use v6;

my $start_time = now;
my $exception;
my $total_lines = 0;

my @files = "c:/testdir".IO.dir(test => / '.' htm $/);
for @files -> $file {
    $total_lines += $file.lines.elems;
    CATCH {
        default { $exception = $_; } #some of the files error out for malformed utf-8
    }
}
say $total_lines;
say now - $start_time;

这在大约3秒内得到577,449的总和.

我如何重写它以利用Perl 6并行思想？我意识到节省的时间不会太多,但它可以作为概念的证明.

Answer 1

use v6;
my $start_time = now;
my $exception;
my @lines;
my $total_lines = 0;

my @files = "c:/testdir".IO.dir(test => / '.' htm $/);
await do for @files -> $file {
    start {
        @lines.push( $file.lines.elems );
        CATCH {
           default { $exception = $_; } #some of the files error out for malformed utf-8
       }
    }
}
$total_lines = [+] @lines;
say $total_lines;
say now - $start_time;