[patch] syntax:plain for .hgignore

[Matt Mackall]

On Wed, Sep 12, 2007 at 08:32:13PM +0200, Guido Ostkamp wrote:
> On Wed, 12 Sep 2007, Matt Mackall wrote:
> 
> >>I'm willing to try it with a tweaked Python 2.5.1 build, however I 
> >>don't know what to change. The 'configure --help' of Python does not 
> >>give any hint.
> >>
> >>Do you have any hints for me what I need to change to have the regex 
> >>module handle larger regular expressions?
> >
> >No idea, nor have I had any luck googling for it.
> 
> I've checked out the Python 2.5.1 sources and found the following:
> 
> The error raised is the following code in .../Python-2.5.1/Modules/_sre.c:
> 
>     for (i = 0; i < n; i++) {
>         PyObject *o = PyList_GET_ITEM(code, i);
>         unsigned long value = PyInt_Check(o) ? (unsigned 
>         long)PyInt_AsLong(o)
>                                               : PyLong_AsUnsignedLong(o);
>         self->code[i] = (SRE_CODE) value;
>         if ((unsigned long) self->code[i] != value) {
> ***         PyErr_SetString(PyExc_OverflowError,
> ***                         "regular expression code size limit exceeded");
>             break;
>         }
>     }
> 
> It appears that an 'unsigned long' value 'value' is stored in 
> 'self->code[i]' which is of type 'unsigned short' because of
> Python-2.5.1/Modules/sre.h which defines SRE_CODE as:
> 
> /* size of a code word (must be unsigned short or larger, and
>    large enough to hold a Py_UNICODE character) */
> #ifdef Py_UNICODE_WIDE
> #define SRE_CODE Py_UCS4
> #else
> #define SRE_CODE unsigned short
> #endif
> 
> I've changed that last SRE_CODE to become 'unsigned long'. After 
> rebuilding Python, I could run your test program successfully.
> 
> However, it remains unclear to me, what 'unicode' has to do with the 
> general size of an regular expression stack. Maybe this is a general 
> Python bug, I don't know.
> 
> Interestingly, although your test program gave basically the same results 
> that you mentioned (= regex was faster), our 'plain' style patch still 
> remains to be faster, even with this Python version.

Can you mail your .hgignore file? Privately and/or obfuscated is fine.

-- 
Mathematics is the supreme nostalgia of our time.