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Remove VARARGS_SENTINEL typemaps further to revision 12666. Note that the idea of having a named typemap for sentinels is flawed unless the named typemap is provided for every single type in the typemap library.

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git-svn-id: https://swig.svn.sourceforge.net/svnroot/swig/trunk@12668 626c5289-ae23-0410-ae9c-e8d60b6d4f22
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William S Fulton 2011-05-14 23:54:09 +00:00
commit aac2b5d2e1
3 changed files with 20 additions and 11 deletions
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20
Doc/Manual/Varargs.html
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@ -381,6 +381,26 @@ a call from the target language which does not provide the maximum number of arg
will generate C code which includes the missing default values, that is, <tt>execlp("a", "b", "c", NULL, NULL)</tt>.
If <tt>compactdefaultargs</tt> is not used, then the generated code will be
<tt>execlp("a", "b", "c")</tt>. The former is useful for helping providing a sentinel to terminate the argument list.
However, this is not guaranteed, for example when a user passes a non-NULL value for all the parameters.
When using <tt>compactdefaultargs</tt> it is possible to guarantee the NULL sentinel is passed through the,
<tt>numinputs=0</tt> <a href="Typemaps.html#Typemaps_nn26">'in' typemap attribute</a>, naming the <b>last parameter</b>.
For example,
</p>
<div class="code">
<pre>
%feature("compactdefaultargs") execlp;
%varargs(3, char *str = NULL) execlp;
%typemap(in, numinputs=0) char *str3 ""
...
int execlp(const char *path, const char *arg, ...);
</pre>
</div>
<p>
Note that <tt>str3</tt> is the name of the last argument, as we have used <tt>%vargars</tt> with 3.
Now <tt>execlp("a", "b", "c", "d", "e")</tt> will result in an error as one too many arguments has been passed,
as now only 2 additional 'str' arguments can be passed with the 3rd one always using the specified default <tt>NULL</tt>.
</p>
<p>