perl6/rakudo：如何更改变量的数据类型？
#!perl6
use v6;
my $m = 70;
my $n = 30;
( $m div $n ).say;
第一个示例有效，但第二个示例无效。我想这是因为在第二个示例中变量值是字符串。如果我的猜测是正确的，我如何将字符串变量更改为整数变量？
#!perl6
use v6;
my $m = '70';
my $n = '30';
( $m div $n ).say;
# No applicable candidates found to dispatch to for 'infix:<div>'.
# Available candidates are:
# :(Int $a, Int $b)
# in main program body at line 7:./perl5.pl
#!perl6
use v6;
my $m = 70;
my $n = 30;
( $m div $n ).say;
The first examples works, but the second doesn't. I suppose it's because in the second example the variable-values are strings. If my guess is right, how could I change the string-variables to integer-variables?
#!perl6
use v6;
my $m = '70';
my $n = '30';
( $m div $n ).say;
# No applicable candidates found to dispatch to for 'infix:<div>'.
# Available candidates are:
# :(Int $a, Int $b)
# in main program body at line 7:./perl5.pl
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评论（2）
你总是可以手动转换为 Int
实际上我希望前缀：<+>会像中那样工作，
但它只是“Num”，并且 sig 需要“Int”，我不确定是否应该这样。
更新：
+$m现在可以工作了。You can always manually cast to Int
Actually I would have hoped that prefix:<+> would work as in
But it just "Num"ifies and the sig requires "Int", I am not sure if it should be this way or not.
UPDATE:
+$mnow works.我有点认为第二种形式也应该有效（首先强制转换为 Int，然后进行整数除法）。我将从其他 Perl 6 开发人员那里得到一些反馈，如果他们同意，我会修复它。 （更新：事实证明 infix: 显然不是强制的，而是指定返回与参数相同类型的值。这通常不适用于 Str）。
正如 Pat 指出的那样，
+$m也应该有效，这是 Rakudo 中长期存在的限制。一般来说，类型的强制转换是通过
$variable.Typename完成的，我相信这适用于当今 Rakudo 中的所有数字类型。I kinda think that the second form should work too (coerce to Int first, and then do integer division). I'll get some feedback from the other Perl 6 developers, and fix it if they agree. (Update: turns out that infix: is explicitly not coercive, but rather is specced to return a value of the same type as the arguments. Which won't work for generally for Str).
As Pat pointed out,
+$mshould also work, that's a long standing limitation in Rakudo.In general, coercion to a type is done with
$variable.Typename, and I believe this works for all numeric types in Rakudo today.