为什么语法`&name arg1 arg2 ...`不能用来调用Perl子程序？

Question

对于Perl子例程,如果传递0参数,我可以使用4个表单来调用它.但是如果传递一个或多个参数,有一个我不能使用的表单,请看下面:

sub name
{
    print "hello\n";
}
# 4 forms to call
name;
&name;
name();
&name();

sub aname
{
        print "@_\n";
}
aname "arg1", "arg2";
#&aname "arg1", "arg2"; # syntax error
aname("arg1", "arg2");
&aname("arg1", "arg2");

错误输出是

String found where operator expected at tmp1.pl line 16, near "&aname "arg1""
    (Missing operator before  "arg1"?)
syntax error at tmp1.pl line 16, near "&aname "arg1""
Execution of tmp1.pl aborted due to compilation errors.

有人可以从编译器的角度解释错误输出吗？我不明白为什么抱怨缺少操作员.

谢谢

Answer 1

它在perlsub中有记录:

要调用子例程:

       NAME(LIST);    # & is optional with parentheses.
       NAME LIST;     # Parentheses optional if predeclared/imported.
       &NAME(LIST);   # Circumvent prototypes.
       &NAME;         # Makes current @_ visible to called subroutine.

有了&NAME "arg",perl看到了&NAME() "ARG",所以它认为在子呼叫和"ARG"之间缺少一个运营商.

在Perl 5中,&大多数情况下不需要.