#!/usr/bin/perl
use warnings;
my %hash=("no1"=>1,
"no2"=>2,
);
print %hash; #Prints no11no22
print "%hash"; #Prints %hash
Why doesn't Perl support interpolation of a hash within double quotes? It supports interpolation for scalars ($), arrays (@) then why not for ha开发者_高级运维shes (%)?
To quote Nathan Torkington: "The big problem is that % is heavily used in double-quoted strings with printf." More information is here.
How should a hash stringify? Scalars are obvious and arrays too. But what should a hash be? How useful will such a stringification be? Is it more or less useful than being able to use a % character unescaped in an interpolating string? Is it worth the amount of work it will take to fix all of the code that uses % in interpolated strings today?
If you can come up with good answers to these questions, then I am sure P5P would be willing to listen to them.
Not really an answer to the "why", but I thought I would point out various answers to the "how".
One could, of course, try:
#!/usr/bin/perl
use warnings; use strict;
my %hash = (
"no1" => 1,
"no2" => 2,
);
print "@{[ %hash ]}\n";
But, I don't know what use that would be.
If you want to dump the contents of a hash or any other complicated data structure, use Data::Dumper or YAML or JSON depending on your use case.
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