Perl6 相当于 Perl 的“存储"或“使用可存储" [英] Perl6 equivalent of Perl's 'store' or 'use Storable'

问题描述

我正在尝试将写入速度非常慢的哈希写入数据文件，但我不确定 Perl6 与 Perl5 相比如何做到这一点.这是一个类似的问题 将中间数据存储在 Perl 6 中的文件中 但我不知道如何使用那里写的任何东西，特别是消息包.

I am attempting to write a hash, which is written very slowly, into a data file, but am unsure about how Perl6 does this in comparison to Perl5. This is a similar question Storing intermediate data in a file in Perl 6 but I don't see how I can use anything written there, specifically messagepack.

我希望看到与 Perl6 等效的

I'd like to see the Perl6 equivalent of

my %hash = ( 'a' => 1, 'b' => 2, 'c' => 3, 'd' => 4);
use Storable;
store \%hash, 'hash.pldata';

然后阅读

my $hashref = retrieve('hash.pldata');
my %hash = %{ $hashref };

这是 Perl5 内置的，超级简单，我不需要安装任何模块(我喜欢它！)，但是我如何在 Perl6 中做到这一点?我在手册中没有看到它.他们似乎在用 STORE https://docs.perl6 谈论其他事情.org/routine/STORE

This is built in to Perl5, it's super easy, I don't need to install any modules (I love it!), but how can I do this in Perl6? I don't see it in the manual. They appear to be talking about something else with STORE https://docs.perl6.org/routine/STORE

推荐答案

这个怎么样?好吧，不如 Storable 有效，但它似乎有效....

How about this? OK, not as efficient as Storable but it seems to work....

#!/usr/bin/perl6
my $hash_ref = {
    array  => [1, 2, 3],
    hash   => { a => 1, b => 2 },
    scalar => 1,
};

# store
my $fh = open('dummy.txt', :w)
    or die "$!\n";
$fh.print( $hash_ref.perl );
close($fh)
    or die "$!\n";

# retrieve
$fh = open('dummy.txt', :r)
    or die "$!\n";
my $line = $fh.get;
close($fh)
    or die "$!\n";

my $new_hash_ref;
{
    use MONKEY-SEE-NO-EVAL;
    $new_hash_ref = EVAL($line)
        or die "$!\n";
}

say "OLD: $hash_ref";
say "NEW: $new_hash_ref";

exit 0;

我明白了

$ perl6 dummy.pl
OLD: array      1 2 3
hash    a       1
b       2
scalar  1
NEW: array      1 2 3
hash    a       1
b       2
scalar  1

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