Michael Stefaniuc wrote:
> Julia Lawall wrote:
>> On Thu, 9 Feb 2012, Michael Stefaniuc wrote:
>>
>>> Hello,
>>>
>>> the type of an expression metavariable when passed to python is
>>> <type 'instance'>
>>> but an expression list gets flattened to a string aka
>>> <type 'str'>
>> Perhaps. I was hoping to get rid of the instance idea, as I don't see
>> the point of having anything other than string, ast least if itis not
>> going to contain any useful information.
> Well, yeah it is just a wrapper object around a string. An array of
> strings would be fine too for the expression list. I was thinking to do
> simple regexp matches against the expression thus avoiding any parsing
> of the expression. With a flat string for the whole expression I cannot
Duh ... I meant "flat string for the whole expression list"
bye
michael
> do that any longer.
>
>
>>> Can the expression list be passed instead as a list/array of 'instance'?
>>> That way one could get to the expressions without having to write a
>>> (simplified) C parser in python.
>>>
>>> What I'm trying to do is to add additional checks to the Wine debug
>>> functions ERR/FIXME/TRACE/WARN. Those are printf style functions with
>>> varargs. While they do use __attribute__(format) there are stricter
>>> checks that can be done for those. But those require the parsing of the
>>> format string and thus the need to go through python.
>> Could another option be to process the arguments individually? I'm not
>> sure to understand how the __attribute__(format) fits in, but if one
>> considers the normal printf, then one could write
>>
>> @@
>> expression str,e;
>> expression list[n] es;
>> @@
>>
>> printf(str,es,e,...)
>>
>> Then afterwards one could inherit n, and use that to check that the
>> corresponding ยค directive in str is compatible with e.
> Yes, I had that initially but then I'll hit the python rule a lot more
> often which from past experience can be a severe performance penalty.
> Though I need to measure this to see how big the impact is.
>
> Also I'll need to cache the parsed format string to not have to re-parse
> it over and over. But that is trivial to do and I planned to do it
> anyway as some format strings are very common.
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