Moose、Try::Tiny 和 TryCatch 的奇怪行为
我刚刚开始与 Moose 合作，遇到了一个我无法解决的奇怪问题。以下代码：
#!/usr/bin/env perl
use strict;
use warnings;
use Try::Tiny;
{
package Foo;
use Moose;
has x => ( is => 'ro', isa => 'Int' );
}
my $f;
try {
$f = Foo->new(x => 'x');
} catch {
die "oops\n";
}
print $f->x . "\n";
产生：
Can't call method "x" on an undefined value at m2.pl line 19.
但是，如果我用 TryCatch 替换 Try::Tiny，它的行为就像我假设的那样：
oops
即使 x > 是正确的值，比如 5，Try::Tiny 仍然会产生 undefined value 错误。
由于我阅读的所有 Moose 文档都使用 Try::Tiny，我很困惑为什么这段代码不起作用。我在这里做错了什么吗？
I've just started working with Moose and have run into an odd problem that I cannot figure out. The following code:
#!/usr/bin/env perl
use strict;
use warnings;
use Try::Tiny;
{
package Foo;
use Moose;
has x => ( is => 'ro', isa => 'Int' );
}
my $f;
try {
$f = Foo->new(x => 'x');
} catch {
die "oops\n";
}
print $f->x . "\n";
produces:
Can't call method "x" on an undefined value at m2.pl line 19.
However, if I replace Try::Tiny with TryCatch, it acts as I would assume it should:
oops
Even if x is the correct value, say 5, Try::Tiny still produces the undefined value error.
As all of the Moose documentation I have been reading uses Try::Tiny, I'm very confused on why this code isn't working. Am I doing something completely wrong here?
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Try::Tiny需要在 try/catch 节末尾有一个分号：这是由于
Try::Tiny的实现 --try 和 catch 都只是函数。Try::Tinyrequires a semicolon at the end of a try/catch stanza:This is due to the implementation of
Try::Tiny--tryandcatchare both just functions.try { ... } catch { ... } 不是内置函数（因为它是由模块提供的）。在 perl 5 中，这意味着您必须以分号结尾，如下所示：
我无法回答 TryCatch 如何设法处理丢失的分号 - 但可以使用各种黑魔法:)
try { ... } catch { ... } isn't a builtin (since it is provided by a module). In perl 5 this means that you have to end it with a semicolon like so:
I can't answer how TryCatch manages to handle the missing semicolon - but it is possible using various black magic :)