无法理解Perl哈希排序的行为

Question

我是Perl的初学者,我试图从"Beginning Perl:Curtis Poe"运行这个示例

#!/perl/bin/perl

use strict;
use warnings;
use diagnostics;

my $hero = 'Ovid';
my $fool = $hero;
print "$hero isn't that much of a hero. $fool is a fool.\n";

$hero = 'anybody else';
print "$hero is probably more of a hero than $fool.\n";

my %snacks = (
    stinky   => 'limburger',
    yummy    => 'brie',
    surprise => 'soap slices',
);
my @cheese_tray = values %snacks;
print "Our cheese tray will have: ";
for my $cheese (@cheese_tray) {
    print "'$cheese' ";
}
print "\n";

当我在带有ActivePerl的windows7系统和codepad.org上试用时,输出上面的代码

Ovid isn't that much of a hero. Ovid is a fool. 
anybody else is probably more of a hero than Ovid.
Our cheese tray will have: 'limburger''soap slices''brie'

我不清楚第三行是打印'limburger''soap slices''brie'但哈希顺序是'limburger''brie''soap slices'.

请帮我理解.

Answer 1

哈希不订购.如果需要特定订单,则需要使用数组.

例如:

my @desc = qw(stinky yummy surprise);
my @type = ("limburger", "brie", "soap slices");
my %snacks;
@snacks{@desc} = @type;

现在你有了类型@type.

你当然也可以使用sort:

my @type = sort keys %snacks;

Answer 2

perldoc perldata:

散列是由其关联的字符串键索引的标量值的无序集合.

您可以根据需要对键或值进行排序.