多次绑定变量

Question

我可以多次绑定一个变量吗？我自己尝试一下,但我不确定语法.我想将一个哈希绑定到Cache :: Memcached :: Tie 和 IPC :: Shareable.

Answer 1

不.确认bvr的猜测,一个变量只能有一个"绑定"魔法.当您调用tie已绑定的变量时,在创建新的tie之前,将丢弃现有的tie-magic(以及关联的绑定对象).

玩具示例:

package Foo;
sub TIESCALAR { return bless [] }
sub DESTROY { print "Destroying Foo\n" }

package Bar;
sub TIESCALAR { return bless [] }
sub DESTROY { print "Destroying Bar\n" }

package main;
tie my $var, "Foo";
print "Tied to ", ref tied $var, "\n";
tie $var, "Bar";
print "Tied to ", ref tied $var, "\n";

输出:

Tied to Foo
Destroying Foo
Tied to Bar
Destroying Bar