Doc tweaks.

[p5sagit/p5-mst-13.2.git] / pod / perlxs.pod

diff --git a/pod/perlxs.pod b/pod/perlxs.pod
index 78e3e7c..ddc9a11 100644 (file)
--- a/pod/perlxs.pod
+++ b/pod/perlxs.pod
@@ -1190,6 +1190,14 @@ prototypes.
           timep
           RETVAL
 
+If the prototypes are enabled, you can disable it locally for a given
+XSUB as in the following example:
+
+    void
+    rpcb_gettime_noproto()
+        PROTOTYPE: DISABLE
+    ...
+
 =head2 The ALIAS: Keyword
 
 The ALIAS: keyword allows an XSUB to have two or more unique Perl names
@@ -1214,6 +1222,40 @@ C<BAR::getit()> for this function.
         OUTPUT:
           timep
 
+=head2 The OVERLOAD: Keyword
+
+Instead of writing an overloaded interface using pure Perl, you
+can also use the OVERLOAD keyword to define additional Perl names
+for your functions (like the ALIAS: keyword above).  However, the
+overloaded functions must be defined with three parameters (except
+for the nomethod() function which needs four parameters).  If any
+function has the OVERLOAD: keyword, several additional lines
+will be defined in the c file generated by xsubpp in order to 
+register with the overload magic.
+
+Since blessed objects are actually stored as RV's, it is useful
+to use the typemap features to preprocess parameters and extract
+the actual SV stored within the blessed RV. See the sample for
+T_PTROBJ_SPECIAL below.
+
+To use the OVERLOAD: keyword, create an XS function which takes
+three input parameters ( or use the c style '...' definition) like
+this:
+
+    SV *
+    cmp (lobj, robj, swap)
+    My_Module_obj    lobj
+    My_Module_obj    robj
+    IV               swap
+    OVERLOAD: cmp <=>
+    { /* function defined here */}
+
+In this case, the function will overload both of the three way
+comparison operators.  For all overload operations using non-alpha
+characters, you must type the parameter without quoting, seperating
+multiple overloads with whitespace.  Note that "" (the stringify 
+overload) should be entered as \"\" (i.e. escaped).
+
 =head2 The INTERFACE: Keyword
 
 This keyword declares the current XSUB as a keeper of the given