New Lua examples - Mark Gossage patch #1295168

git-svn-id: https://swig.svn.sourceforge.net/svnroot/swig/trunk@7471 626c5289-ae23-0410-ae9c-e8d60b6d4f22

SWIG/Examples/lua/pointer/Makefile

@@ -0,0 +1,19 @@
+TOP        = ../..
+SWIG       = $(TOP)/../swig
+CXXSRCS    = example.c
+TARGET     = example
+INTERFACE  = example.i
+LIBS       = 
+
+all::
+	$(MAKE) -f $(TOP)/Makefile CXXSRCS='$(CXXSRCS)' SWIG='$(SWIG)' \
+	TARGET='$(TARGET)' INTERFACE='$(INTERFACE)' lua
+
+static::
+	$(MAKE) -f $(TOP)/Makefile CXXSRCS='$(CXXSRCS)' SWIG='$(SWIG)' \
+	TARGET='mylua' INTERFACE='$(INTERFACE)' lua_static
+
+clean::
+	$(MAKE) -f $(TOP)/Makefile lua_clean
+
+check: all

SWIG/Examples/lua/pointer/example.c

@@ -0,0 +1,16 @@
+/* File : example.c */
+
+void add(int *x, int *y, int *result) {
+  *result = *x + *y;
+}
+
+void sub(int *x, int *y, int *result) {
+  *result = *x - *y;
+}
+
+int divide(int n, int d, int *r) {
+   int q;
+   q = n/d;
+   *r = n - q*d;
+   return q;
+}

SWIG/Examples/lua/pointer/example.i

@@ -0,0 +1,28 @@
+/* File : example.i */
+%module example
+
+%{
+   #include <stdlib.h>
+%}
+
+/* This example illustrates a couple of different techniques
+   for manipulating C pointers */
+
+/* First we'll use the pointer library */
+extern void add(int *x, int *y, int *result);
+%include cpointer.i
+%pointer_functions(int, intp);
+
+/* Next we'll use some typemaps */
+
+%include typemaps.i
+extern void sub(int *INPUT, int *INPUT, int *OUTPUT);
+
+/* Next we'll use typemaps and the %apply directive */
+
+%apply int *OUTPUT { int *r };
+extern int divide(int n, int d, int *r);
+
+
+
+

SWIG/Examples/lua/pointer/runme.lua

@@ -0,0 +1,48 @@
+---- importing ----
+if string.sub(_VERSION,1,7)=='Lua 5.0' then
+	-- lua5.0 doesnt have a nice way to do this
+	lib=loadlib('example.dll','Example_Init') or loadlib('example.so','Example_Init')
+	assert(lib)()
+else
+	-- lua 5.1 does
+	require('example')
+end
+
+-- First create some objects using the pointer library.
+print("Testing the pointer library")
+a = example.new_intp()
+b = example.new_intp()
+c = example.new_intp()
+example.intp_assign(a,37)
+example.intp_assign(b,42)
+
+print("     a = "..tostring(a))
+print("     b = "..tostring(b))
+print("     c = "..tostring(c))
+
+-- Call the add() function with some pointers
+example.add(a,b,c)
+
+-- Now get the result
+r = example.intp_value(c)
+print("     37 + 42 = "..r)
+
+-- Clean up the pointers
+-- since this is C-style pointers you must clean it up
+example.delete_intp(a)
+example.delete_intp(b)
+example.delete_intp(c)
+
+-- Now try the typemap library
+-- This should be much easier. Now how it is no longer
+-- necessary to manufacture pointers.
+
+print("Trying the typemap library")
+r = example.sub(37,42)
+print("     37 - 42 = "..r)
+
+-- Now try the version with multiple return values
+
+print("Testing multiple return values")
+q,r = example.divide(42,37)
+print("     42/37 = "..q.." remainder "..r)