如何在 Perl 中比较两个哈希而不使用 Data::Compare？
最佳方法根据您的目的而有所不同。 Sinan 提到的常见问题解答项目是一个很好的资源：如何测试两个数组或哈希是否相等？。在开发和调试过程中（当然还有编写单元测试时），我发现
Test::Moreuse strict;
use warnings;
my %some_data = (
a => [1, 2, 'x'],
b => { foo => 'bar', biz => 'buz' },
j => '867-5309',
);
my %other_data = (
a => [1, 2, 'x'],
b => { foo => 'bar', biz => 'buz' },
j => '867-5309x',
);
use Test::More tests => 1;
is_deeply(\%other_data, \%some_data, 'data structures should be the same');
输出：
1..1
not ok 1 - data structures should be the same
# Failed test 'data structures should be the same'
# at _x.pl line 19.
# Structures begin differing at:
# $got->{j} = '867-5309x'
# $expected->{j} = '867-5309'
# Looks like you failed 1 test of 1.
在谈论哈希时，比较不是一个足够详细的短语。比较哈希值的方法有很多：
它们的钥匙数量相同吗？
if (%a == %b) {
print "they have the same number of keys\n";
} else {
print "they don't have the same number of keys\n";
}
两个哈希中的键是否相同？
if (%a != %b) {
print "they don't have the same number of keys\n";
} else {
my %cmp = map { $_ => 1 } keys %a;
for my $key (keys %b) {
last unless exists $cmp{$key};
delete $cmp{$key};
}
if (%cmp) {
print "they don't have the same keys\n";
} else {
print "they have the same keys\n";
}
}
它们在两个哈希中是否具有相同的键和相同的值？
if (%a != %b) {
print "they don't have the same number of keys\n";
} else {
my %cmp = map { $_ => 1 } keys %a;
for my $key (keys %b) {
last unless exists $cmp{$key};
last unless $a{$key} eq $b{$key};
delete $cmp{$key};
}
if (%cmp) {
print "they don't have the same keys or values\n";
} else {
print "they have the same keys or values\n";
}
}
它们是同构的吗（我将把这个问题留给读者，因为我并不是特别想尝试从头开始实现它）？
或者其他一些平等的衡量标准？
当然，这段代码只处理简单的哈希值。添加复杂的数据结构使其变得更加复杂。
Test::Deep::NoTest 具有相同的功能。
Perl 的常见问题解答和答案是 Perl 发行版的一部分。您可以通过运行以下命令查看您的
perl$ perldoc -q equal在您的终端中。
快速、肮脏，而且我确信效率不高：
use strict;
use warnings;
use Data::Dumper;
sub compare ($$) {
local $Data::Dumper::Terse = 1;
local $Data::Dumper::Indent = 0;
Dumper(shift) eq Dumper(shift);
}
my %a = ( foo => 'bar', bar => [ 0 .. 3 ] );
my %b = ( foo => 'bar', bar => [ 0 .. 3 ] );
my %c = ( foo => 'bar', bar => [ 0 .. 4 ] );
print Dumper compare \%a, \%b;
print Dumper compare \%a, \%c;
use strict;
use warnings;
use JSON::XS;
my $some_data ={
a => [1, 2, 'x'],
b => { foo => 'bar', biz => 'buz' },
j => '867-5309',
};
my $other_data = {
a => [1, 2, 'x'],
b => { foo => 'bar', biz => 'buz' },
j => '867-5309x',
};
use Test::More tests => 1;
is_deeply(JSON::XS->new->canonical( 1 )->utf8->encode($other_data), JSON::XS->new->canonical( 1 )->utf8->encode($some_data), 'data structures should be the same');
示例
# Failed test 'data structures should be the same'
# at ./t/a.t line 18.
# got: '{"a":[1,2,"x"],"b":{"biz":"buz","foo":"bar"},"j":"867-5309x"}'
# expected: '{"a":[1,2,"x"],"b":{"biz":"buz","foo":"bar"},"j":"867-5309"}'
# Looks like you failed 1 test of 1.
用于比较：
sub HashCompare {
my ( $a, $b ) = @_;
my %rhash_1 = %$a;
my %rhash_2 = %$b;
my $key = undef;
my $hash_2_line = undef;
my $hash_1_line = undef;
foreach $key ( keys(%rhash_2) ) {
if ( exists( $rhash_1{$key} ) ) {
if ( $rhash_1{$key} ne $rhash_2{$key} ) {
print "key $key in $file_1 = $rhash_1{$key} & $rhash_2{$key} in $file_2\n";
}
}
}
else {
print "key $key in $file_1 is not present in $file_2\n";
#next;
}
}
foreach my $comp_key ( keys %rhash_1 ) {
if ( !exists( $rhash_2{$comp_key} ) ) {
print MYFILE "key $comp_key in $file_2 is not present in $file_1\n";
}
}
return;
}
创建没有重复键的哈希：
sub CreateHash {
my (@key_val_file ) = @_;
my $key_count = 1;
my %hash_key_val = ();
my $str4 = undef;
local $/ = undef;
foreach my $each_line (@key_val_file) {
@key_val = split( /,/, $each_line );
if ( exists( $hash_key_val{$key_val[0]} ) ) {
$key_count = $key_count + 1;
$str4 = $key_val[0] . " occurence-" . $key_count;
$hash_key_val{$str4} = $key_val[1];
}
else {
$hash_key_val{$key_name} = $key_val[1];
}
}
}
$key_count = 1;
close FILE;
return %hash_key_val;
}