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Diffstat (limited to 'Examples/python/class/index.html')
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1 files changed, 14 insertions, 73 deletions
diff --git a/Examples/python/class/index.html b/Examples/python/class/index.html index 12c5eded1..2e1baa395 100644 --- a/Examples/python/class/index.html +++ b/Examples/python/class/index.html @@ -12,9 +12,7 @@ <H2>Wrapping a simple C++ class</H2> <p> -This example illustrates the most primitive form of C++ class wrapping performed -by SWIG. In this case, C++ classes are simply transformed into a collection of -C-style functions that provide access to class members. +This example illustrates wrapping a simple C++ class to give a Python class. <h2>The C++ Code</h2> @@ -32,8 +30,8 @@ public: } virtual ~Shape() { nshapes--; - }; - double x, y; + } + double x, y; void move(double dx, double dy); virtual double area() = 0; virtual double perimeter() = 0; @@ -44,7 +42,7 @@ class Circle : public Shape { private: double radius; public: - Circle(double r) : radius(r) { }; + Circle(double r) : radius(r) { } virtual double area(); virtual double perimeter(); }; @@ -53,7 +51,7 @@ class Square : public Shape { private: double width; public: - Square(double w) : width(w) { }; + Square(double w) : width(w) { } virtual double area(); virtual double perimeter(); }; @@ -102,52 +100,35 @@ c = example.new_Circle(10.0) </blockquote> <p> -<li>To access member data, a pair of accessor functions are used. +<li>Member variables of the C++ class are wrapped as attributes of the Python class. For example: <blockquote> <pre> -example.Shape_x_set(c,15) # Set member data -x = example.Shape_x_get(c) # Get member data +c.x = 15 # Set member data +x = c.x # Get member data </pre> </blockquote> -Note: when accessing member data, the name of the class in which -the member data was must be used. In this case, <tt>Shape_x_get()</tt> -and <tt>Shape_x_set()</tt> are used since 'x' was defined in Shape. - <p> -<li>To invoke a member function, you simply do this +<li>Member function are invoked as you would expect: <blockquote> <pre> -print "The area is ", example.Shape_area(c) +print "The area is ", c.area() </pre> </blockquote> <p> -<li>Type checking knows about the inheritance structure of C++. For example: +<li>To invoke a destructor, simply call <code>del</code> on the object: <blockquote> <pre> -example.Shape_area(c) # Works (c is a Shape) -example.Circle_area(c) # Works (c is a Circle) -example.Square_area(c) # Fails (c is definitely not a Square) +del c # Deletes a shape </pre> </blockquote> <p> -<li>To invoke a destructor, simply do this - -<blockquote> -<pre> -example.delete_Shape(c) # Deletes a shape -</pre> -</blockquote> - -(Note: destructors are currently not inherited. This might change later). - -<p> <li>Static member variables are wrapped as C global variables. For example: <blockquote> @@ -162,52 +143,12 @@ example.cvar.Shapes_nshapes = 13 # Set a static data member <h2>General Comments</h2> <ul> -<li>This low-level interface is not the only way to handle C++ code. -Proxy classes provide a much higher-level interface. - -<p> -<li>SWIG *does* know how to properly perform upcasting of objects in +<li>SWIG <b>does</b> know how to properly perform upcasting of objects in an inheritance hierarchy (including multiple inheritance). Therefore it is perfectly safe to pass an object of a derived class to any function involving a base class. -<p> -<li>A wide variety of C++ features are not currently supported by SWIG. Here is the -short and incomplete list: - -<p> -<ul> -<li>Overloaded methods and functions. SWIG wrappers don't know how to resolve name -conflicts so you must give an alternative name to any overloaded method name using the -%name directive like this: - -<blockquote> -<pre> -void foo(int a); -%name(foo2) void foo(double a, double b); -</pre> -</blockquote> - -<p> -<li>Overloaded operators. Not supported at all. The only workaround for this is -to write a helper function. For example: - -<blockquote> -<pre> -%inline %{ - Vector *vector_add(Vector *a, Vector *b) { - ... whatever ... - } -%} -</pre> -</blockquote> - -<p> -<li>Namespaces. Not supported at all. Won't be supported until SWIG2.0 (if at all). - -<p> -<li>Dave's snide remark: Like a large bottle of strong Tequilla, it's better to -use C++ in moderation. +<li>C++ Namespaces - %nspace isn't yet supported for Python. </ul> |
