1 Dec
2019
1 Dec
'19
4:35 a.m.
Why is it that $null + 0 is 0 but not int? What is it?
-- Juha
$avp(test) = $null + 0;
if (is_int("$avp(test)"))
INFO(test $avp(test) IS int);
else
INFO(test $avp(test) IS NOT int);
Dec 1 02:46:01 salmon /usr/bin/sip-proxy[10138]: INFO: test 0 IS NOT int
1 Dec
1 Dec
12:08 p.m.
Probably is string, that's the default value type of PVs, as they
originated from xlog, where the output was a string to be printed.
"" + 0 should be "0"
Cheers,
Daniel
On 01.12.19 02:35, Juha Heinanen wrote:
Why is it that $null + 0 is 0 but not int? What is
it?
-- Juha
$avp(test) = $null + 0;
if (is_int("$avp(test)"))
INFO(test $avp(test) IS int);
else
INFO(test $avp(test) IS NOT int);
Dec 1 02:46:01 salmon /usr/bin/sip-proxy[10138]: INFO: test 0 IS NOT int
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--
Daniel-Constantin Mierla -- www.asipto.com
www.twitter.com/miconda -- www.linkedin.com/in/miconda
Kamailio World Conference - April 27-29, 2020, in Berlin -- www.kamailioworld.com
2:29 p.m.
I added 0 to $null in order to get int. If I had added "0" the result should be
string. So this looks like a bug to me. If I add 0, result can't be string.
Juha
On December 1, 2019 6:08:01 PM GMT+09:00, Daniel-Constantin Mierla
<miconda(a)gmail.com> wrote:
Probably is string, that's the default value type
of PVs, as they
originated from xlog, where the output was a string to be printed.
"" + 0 should be "0"
Cheers,
Daniel
On 01.12.19 02:35, Juha Heinanen wrote:
Why is it that $null + 0 is 0 but not int? What
is it?
-- Juha
$avp(test) = $null + 0;
if (is_int("$avp(test)"))
INFO(test $avp(test) IS int);
else
INFO(test $avp(test) IS NOT int);
Dec 1 02:46:01 salmon /usr/bin/sip-proxy[10138]: INFO: test 0 IS NOT
int
>
> _______________________________________________
> Kamailio (SER) - Users Mailing List
> sr-users(a)lists.kamailio.org
> https://lists.kamailio.org/cgi-bin/mailman/listinfo/sr-users
4:26 p.m.
In all programming languages the first operand gives the type of the
expression. That's why it works to concatenate integers to string in the
fashion:
"abc" + 123
Try 0 + $null and see if it is integer.
Cheers,
Daniel
On 01.12.19 12:29, Juha Heinanen wrote:
I added 0 to $null in order to get int. If I had added
"0" the result should be string. So this looks like a bug to me. If I add 0,
result can't be string.
Juha
On December 1, 2019 6:08:01 PM GMT+09:00, Daniel-Constantin Mierla
<miconda(a)gmail.com> wrote:
> Probably is string, that's the default value type of PVs, as they
> originated from xlog, where the output was a string to be printed.
>
> "" + 0 should be "0"
>
> Cheers,
> Daniel
>
> On 01.12.19 02:35, Juha Heinanen wrote:
>> Why is it that $null + 0 is 0 but not int? What is it?
>>
>> -- Juha
>>
>> $avp(test) = $null + 0;
>> if (is_int("$avp(test)"))
>> INFO(test $avp(test) IS int);
>> else
>> INFO(test $avp(test) IS NOT int);
>>
>> Dec 1 02:46:01 salmon /usr/bin/sip-proxy[10138]: INFO: test 0 IS NOT
> int
>> _______________________________________________
>> Kamailio (SER) - Users Mailing List
>> sr-users(a)lists.kamailio.org
>> https://lists.kamailio.org/cgi-bin/mailman/listinfo/sr-users
--
Daniel-Constantin Mierla -- www.asipto.com
www.twitter.com/miconda -- www.linkedin.com/in/miconda
Kamailio World Conference - April 27-29, 2020, in Berlin -- www.kamailioworld.com
2 Dec
2 Dec
5:50 a.m.
Thanks for the tip. 0 + $null is int. The bug is that $null should be nothing, not an
empty string.
-- Juha
10:58 a.m.
It was like this from the beginning, there is a base string type for
variables by default.
If people want, then we can reconsider when doing a major
refactoring/adjustment to the native interpreter, probably for Kamailio
6.0, as there were some discussions during the last Kamailio Developers
Meeting in Dusseldorf and informed to mailing lists.
However, that can result in no-operations with $null values, like it
happens now in Lua or Python -- if you want to print or use in
expressions NULL, you get an exception, stopping execution of the script
for the respective SIP message. That is the reason KEMI has
KSR.pv.gete() to return empty string when the value is $null, otherwise
the external scripting interpreters throw errors/exceptions when using
NULL in expressions.
I still thing that having a loose handling of $null is better that
string evaluation to "nothing" -- it can result in a lot of IF
conditions to evaluate if a variable can be used in an expression or log
or other functions parameters. But again, it can be discussed and
reconsidered.
Cheers,
Daniel
On 02.12.19 03:50, Juha Heinanen wrote:
Thanks for the tip. 0 + $null is int. The bug is that
$null should be nothing, not an empty string.
-- Juha
--
Daniel-Constantin Mierla -- www.asipto.com
www.twitter.com/miconda -- www.linkedin.com/in/miconda
Kamailio World Conference - April 27-29, 2020, in Berlin -- www.kamailioworld.com
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Daniel-Constantin Mierla -
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