我想得到一个指向对象方法的指针,例如这个类
class Foo {
has $thing = "baz";
method bar() { say $thing }
};
sub quux( Callable $flimflam ) {
$flimflam()
};
my $foo = Foo.new;
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我想抓住$foo.bar方法指针将它传递给quux.但是,这个
quux(&($foo.bar))
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失败了 Type check failed in binding to parameter '$flimflam'; expected Callable but got Bool (Bool::True)? in sub quux
这也不起作用
quux($foo.bar)
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也许是因为它没有参数; 但是,如果我们将定义更改bar为:
method bar($some ) { say $some ~ $thing }
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然后上面调用Too few positionals passed; expected 2 arguments but got 1? in …
我正在尝试用Perl 6编写一些类来测试Perl 6类和方法.
这是代码:
class human1 {
method fn1() {
print "#from human1.fn1\n";
}
}
class human2 {
method fn1() {
print "#from human2.fn1\n";
}
}
my $a = human1.new();
my $b = human2.new();
$a.fn1();
$b.fn1();
print "now trying more complex stuff\n";
my $hum1_const = &human1.new;
my $hum2_const = &human2.new;
my $c = $hum2_const();
$c.fn1();
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基本上我希望能够使用human1构造函数或human2构造函数来$c动态构建对象.但是我收到以下错误:
Error while compiling /usr/bhaskars/code/perl/./a.pl6
Illegally post-declared types:
human1 used at line 23
human2 used at line 24
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如何 …