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From: Justin C on 22 Jul 2010 11:37
On 2010-07-22, Justin C <justin.1007(a)purestblue.com> wrote:
> I'm trying to avoid warnings in my Apache logs. Here's the code that's
> causing the problem:
>
> unless ($methods->{$param{method}}) {
> $param{method} = "default";
> }
>
> If the web-page in question is called without any parameters then
> $param{method} is undef, in which case I want $param->{method} =
> "default".
>
> When the page is called with parameters all is OK.
>
> What is a better way of doing the above to avoid "Use of uninitialized
> value $param{"method"}" ?

Thanks to Jens and Wolf. Between you both you spotted a flaw in my code
and provided the work-around.

And sln, I think the last two of your suggestions were 5.10 solutions,
these are operators I've yet to explore, though I can see, from your
explanation, what each is doing. I'll investigate them further.

Justin.

--
Justin C, by the sea.
From: Justin C on 23 Jul 2010 04:41
On 2010-07-22, sln(a)netherlands.com <sln(a)netherlands.com> wrote:
> On Thu, 22 Jul 2010 14:34:08 +0100, Justin C <justin.1007(a)purestblue.com> wrote:
>
>>I'm trying to avoid warnings in my Apache logs. Here's the code that's
>>causing the problem:
>>
>>unless ($methods->{$param{method}}) {
>> $param{method} = "default";
>>}
>>
>>If the web-page in question is called without any parameters then
>>$param{method} is undef, in which case I want $param->{method} =
>>"default".
>>
>>When the page is called with parameters all is OK.
>>
>>What is a better way of doing the above to avoid "Use of uninitialized
>>value $param{"method"}" ?
>>
>> Justin.
>
> Depends on what you want:
>
> # (undef,'') fail ; (0) pass
> unless (defined $param{method} and length $param{method}) {
> $param{method} = "default";
> }
> # (undef,0,'') fail
> $param{method} ||= "default";
>
> # (undef) fail ; (0,'') pass
> $param{method} //= "default";

What I want is to test that $param{method} is a valid method (if it has
been supplied at all). If it's not a valid method, or is not defined,
then it is to be set to "default".

I've gone with (line wrapped to avoid break):
$param{method} = "default"
unless ( ($param{method}) && ($methods->{$param{method}}) );

This avoids the "Use of uninitialized.." in my Apache logs.

I'm trying to get my head around '||=' and '//=', they're great
shortcuts, I've just got to use them a few times to get it set in my
head.

Justin.

--
Justin C, by the sea.
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