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ru.cgi.perl
- RU.CGI.PERL ------------------------------------------------------------------
From : Andrey Sapozhnikov 2:5020/400 15 May 2003 17:33:10
To : Roman Kirjanov
Subject : Re: Константы и ключи хэша
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Roman Kirjanov wrote:
> Hello, All!
>
> my %hash = ('one' => 'один', 'FOO' => 'This is FOO');
> use constant FOO => 'one';
> print $hash{FOO};
>
> Можно ли как-нить добиться результатов, как от print $hash{(FOO)}; ну там
> переменную какую внутреннюю, use какой-нить. Hе нравится $hash{(FOO)}: этож
> можно и $hash{(((FOO)))} написать - тоже будет работать.
perldoc constant
...
You can get into trouble if you use constants in a context which auto-
matically quotes barewords (as is true for any subroutine call). For
example, you can't say $hash{CONSTANT} because "CONSTANT" will be
interpreted as a string. Use $hash{CONSTANT()} or $hash{+CONSTANT} to
prevent the bareword quoting mechanism from kicking in. Similarly,
since the "=>" operator quotes a bareword immediately to its left, you
have to say "CONSTANT() => 'value'" (or simply use a comma in place of
the big arrow) instead of "CONSTANT => 'value'".
...
--
Андрей
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Re: Константы и ключи хэша