implemented double dispatch for print(); methods are specified with

print_func<C>() options in the GINAC_IMPLEMENT_REGISTERED_CLASS_OPT macro
(see basic.cpp for an example); what remains is to convert all existing
classes to this new scheme...

diff --git a/ginac/basic.cpp b/ginac/basic.cpp
index daac085617d01cb8d1c3d66077a3a82e4317c8e2..66e6c90182cdfef57bc2ccec12ec55c3caa0b43d 100644 (file)
--- a/ginac/basic.cpp
+++ b/ginac/basic.cpp
@@ -36,13 +36,15 @@
 #include "relational.h"
 #include "operators.h"
 #include "wildcard.h"
 #include "relational.h"
 #include "operators.h"
 #include "wildcard.h"

-#include "print.h"

 #include "archive.h"
 #include "utils.h"
 
 namespace GiNaC {
 
 #include "archive.h"
 #include "utils.h"
 
 namespace GiNaC {
 

-GINAC_IMPLEMENT_REGISTERED_CLASS(basic, void)
+GINAC_IMPLEMENT_REGISTERED_CLASS_OPT(basic, void,
+  print_func<print_context>(&basic::do_print).
+  print_func<print_tree>(&basic::do_print_tree).
+  print_func<print_python_repr>(&basic::do_print_python_repr))

 
 //////////
 // default constructor, destructor, copy constructor and assignment operator
 
 //////////
 // default constructor, destructor, copy constructor and assignment operator


@@ -116,23 +118,74 @@ void basic::archive(archive_node &n) const
 
 // public
 
 
 // public
 

-/** Output to stream.
+/** Output to stream. This performs double dispatch on the dynamic type of
+ *  *this and the dynamic type of the supplied print context.

  *  @param c print context object that describes the output formatting
  *  @param level value that is used to identify the precedence or indentation
  *               level for placing parentheses and formatting */
 void basic::print(const print_context & c, unsigned level) const
 {
  *  @param c print context object that describes the output formatting
  *  @param level value that is used to identify the precedence or indentation
  *               level for placing parentheses and formatting */
 void basic::print(const print_context & c, unsigned level) const
 {

-       if (is_a<print_tree>(c)) {
+       // Double dispatch on object type and print_context type
+       const registered_class_info * reg_info = &get_class_info();
+       const print_context_class_info * pc_info = &c.get_class_info();

 
 

-               c.s << std::string(level, ' ') << class_name()
-                   << std::hex << ", hash=0x" << hashvalue << ", flags=0x" << flags << std::dec
-                   << ", nops=" << nops()
-                   << std::endl;
-               for (size_t i=0; i<nops(); ++i)
-                       op(i).print(c, level + static_cast<const print_tree &>(c).delta_indent);
+next_class:
+       const std::vector<print_functor> & pdt = reg_info->options.get_print_dispatch_table();

 
 

-       } else
-               c.s << "[" << class_name() << " object]";
+next_context:
+       unsigned id = pc_info->options.get_id();
+       if (id >= pdt.size() || !(pdt[id].is_valid())) {
+
+               // Method not found, try parent print_context class
+               const print_context_class_info * parent_pc_info = pc_info->get_parent();
+               if (parent_pc_info) {
+                       pc_info = parent_pc_info;
+                       goto next_context;
+               }
+
+               // Method still not found, try parent class
+               const registered_class_info * parent_reg_info = reg_info->get_parent();
+               if (parent_reg_info) {
+                       reg_info = parent_reg_info;
+                       pc_info = &c.get_class_info();
+                       goto next_class;
+               }
+
+               // Method still not found. This shouldn't happen because basic (the
+               // base class of the algebraic hierarchy) registers a method for
+               // print_context (the base class of the print context hierarchy),
+               // so if we end up here, there's something wrong with the class
+               // registry.
+               throw (std::runtime_error(std::string("basic::print(): method for ") + class_name() + "/" + c.class_name() + " not found"));
+
+       } else {
+
+               // Call method
+               pdt[id](*this, c, level);
+       }
+}
+
+/** Default output to stream. */
+void basic::do_print(const print_context & c, unsigned level) const
+{
+       c.s << "[" << class_name() << " object]";
+}
+
+/** Tree output to stream. */
+void basic::do_print_tree(const print_tree & c, unsigned level) const
+{
+       c.s << std::string(level, ' ') << class_name()
+           << std::hex << ", hash=0x" << hashvalue << ", flags=0x" << flags << std::dec
+           << ", nops=" << nops()
+           << std::endl;
+       for (size_t i=0; i<nops(); ++i)
+               op(i).print(c, level + c.delta_indent);
+}
+
+/** Python parsable output to stream. */
+void basic::do_print_python_repr(const print_python_repr & c, unsigned level) const
+{
+       c.s << class_name() << "()";

 }
 
 /** Little wrapper around print to be called within a debugger.
 }
 
 /** Little wrapper around print to be called within a debugger.


@@ -156,7 +209,7 @@ void basic::dbgprinttree() const
        this->print(print_tree(std::cerr));
 }
 
        this->print(print_tree(std::cerr));
 }
 

-/** Return relative operator precedence (for parenthizing output). */
+/** Return relative operator precedence (for parenthezing output). */

 unsigned basic::precedence() const
 {
        return 70;
 unsigned basic::precedence() const
 {
        return 70;

diff --git a/ginac/basic.h b/ginac/basic.h
index 90e3faffe2cff79ce3d838d85493bc039a683f94..1bd89caca02177a01eac77aa8a4107cd6a80b17b 100644 (file)
--- a/ginac/basic.h
+++ b/ginac/basic.h
@@ -208,6 +208,11 @@ public:
 
 protected:
        void ensure_if_modifiable() const;
 
 protected:
        void ensure_if_modifiable() const;

+
+private:
+       void do_print(const print_context & c, unsigned level) const;
+       void do_print_tree(const print_tree & c, unsigned level) const;
+       void do_print_python_repr(const print_python_repr & c, unsigned level) const;

        
        // member variables
 protected:
        
        // member variables
 protected:

diff --git a/ginac/power.cpp b/ginac/power.cpp
index 64ebc71746c6162211993db9f59521ec244c668f..fab41d833279cc42d2691ac88f9c5356a106ec0a 100644 (file)
--- a/ginac/power.cpp
+++ b/ginac/power.cpp
@@ -89,7 +89,7 @@ static void print_sym_pow(const print_context & c, const symbol &x, int exp)
 {
        // Optimal output of integer powers of symbols to aid compiler CSE.
        // C.f. ISO/IEC 14882:1998, section 1.9 [intro execution], paragraph 15
 {
        // Optimal output of integer powers of symbols to aid compiler CSE.
        // C.f. ISO/IEC 14882:1998, section 1.9 [intro execution], paragraph 15

-       // to learn why such a parenthisation is really necessary.
+       // to learn why such a parenthesation is really necessary.

        if (exp == 1) {
                x.print(c);
        } else if (exp == 2) {
        if (exp == 1) {
                x.print(c);
        } else if (exp == 2) {

diff --git a/ginac/print.h b/ginac/print.h
index 54b6ca719531b0349174278cd630806c5730618b..6b80d488dded42fbacb017bf8ad7bb53e6c0568b 100644 (file)
--- a/ginac/print.h
+++ b/ginac/print.h
@@ -25,6 +25,7 @@
 
 #include <iosfwd>
 #include <string>
 
 #include <iosfwd>
 #include <string>

+#include <memory>

 
 #include "class_info.h"
 
 
 #include "class_info.h"
 


@@ -67,6 +68,7 @@ public:
 public: \
        typedef supername inherited; \
        friend class function_options; \
 public: \
        typedef supername inherited; \
        friend class function_options; \

+       friend class registered_class_options; \

 private: \
        static GiNaC::print_context_class_info reg_info; \
 public: \
 private: \
        static GiNaC::print_context_class_info reg_info; \
 public: \


@@ -176,6 +178,94 @@ template <class T>
 inline bool is_a(const print_context & obj)
 { return dynamic_cast<const T *>(&obj) != 0; }
 
 inline bool is_a(const print_context & obj)
 { return dynamic_cast<const T *>(&obj) != 0; }
 

+
+class basic;
+
+/** Base class for print_functor handlers */
+class print_functor_impl {
+public:
+       virtual ~print_functor_impl() {}
+       virtual print_functor_impl *duplicate() const = 0;
+       virtual void operator()(const basic & obj, const print_context & c, unsigned level) const = 0;
+};
+
+/** print_functor handler for pointer-to-functions of class T, context type C */
+template <class T, class C>
+class print_ptrfun_handler : public print_functor_impl {
+public:
+       typedef void (*F)(const T &, const C &, unsigned);
+
+       print_ptrfun_handler(F f_) : f(f_) {}
+       print_ptrfun_handler *duplicate() const { return new print_ptrfun_handler(*this); }
+
+       void operator()(const basic & obj, const print_context & c, unsigned level) const
+       {
+               // Call the supplied function
+               f(dynamic_cast<const T &>(obj), dynamic_cast<const C &>(c), level);
+       }
+
+private:
+       F f;
+};
+
+/** print_functor handler for member functions of class T, context type C */
+template <class T, class C>
+class print_memfun_handler : public print_functor_impl {
+public:
+       typedef void (T::*F)(const C & c, unsigned level);
+
+       print_memfun_handler(F f_) : f(f_) {}
+       print_memfun_handler *duplicate() const { return new print_memfun_handler(*this); }
+
+       void operator()(const basic & obj, const print_context & c, unsigned level) const
+       {
+               // Call the supplied member function
+               return (dynamic_cast<const T &>(obj).*f)(dynamic_cast<const C &>(c), level);
+       }
+
+private:
+       F f;
+};
+
+/** This class represents a print method for a certain algebraic class and
+ *  print_context type. Its main purpose is to hide the difference between
+ *  member functions and nonmember functions behind one unified operator()
+ *  interface. print_functor has value semantics and acts as a smart pointer
+ *  (with deep copy) to a class derived from print_functor_impl which
+ *  implements the actual function call. */
+class print_functor {
+public:
+       print_functor() : impl(0) {}
+       print_functor(const print_functor & other) : impl(other.impl.get() ? other.impl->duplicate() : 0) {}
+       print_functor(std::auto_ptr<print_functor_impl> impl_) : impl(impl_) {}
+
+       template <class T, class C>
+       print_functor(void f(const T &, const C &, unsigned)) : impl(new print_ptrfun_handler<T, C>(f)) {}
+
+       template <class T, class C>
+       print_functor(void (T::*f)(const C &, unsigned)) : impl(new print_memfun_handler<T, C>(f)) {}
+
+       print_functor & operator=(const print_functor & other)
+       {
+               if (this != &other) {
+                       print_functor_impl *p = other.impl.get();
+                       impl.reset(p ? other.impl->duplicate() : 0);
+               }
+               return *this;
+       }
+
+       void operator()(const basic & obj, const print_context & c, unsigned level) const
+       {
+               (*impl)(obj, c, level);
+       }
+
+       bool is_valid() const { return impl.get(); }
+
+private:
+       std::auto_ptr<print_functor_impl> impl;
+};
+
+

 } // namespace GiNaC
 
 #endif // ndef __GINAC_BASIC_H__
 } // namespace GiNaC
 
 #endif // ndef __GINAC_BASIC_H__

diff --git a/ginac/registrar.h b/ginac/registrar.h
index 9dc3f24d9f80e6bce4769db892620ab66fa18ae2..9610f6c0f7a7e9fcc66a41c6b3d3b024df3d4a41 100644 (file)
--- a/ginac/registrar.h
+++ b/ginac/registrar.h
@@ -25,8 +25,10 @@
 
 #include <string>
 #include <list>
 
 #include <string>
 #include <list>

+#include <vector>

 
 #include "class_info.h"
 
 #include "class_info.h"

+#include "print.h"

 
 namespace GiNaC {
 
 
 namespace GiNaC {
 


@@ -51,12 +53,42 @@ public:
        const char *get_parent_name() const { return parent_name; }
        unsigned get_id() const { return tinfo_key; }
        unarch_func get_unarch_func() const { return unarchive; }
        const char *get_parent_name() const { return parent_name; }
        unsigned get_id() const { return tinfo_key; }
        unarch_func get_unarch_func() const { return unarchive; }

+       const std::vector<print_functor> &get_print_dispatch_table() const { return print_dispatch_table; }
+
+       template <class Ctx, class T, class C>
+       registered_class_options & print_func(void f(const T &, const C & c, unsigned))
+       {
+               set_print_func(Ctx::reg_info.options.get_id(), f);
+               return *this;
+       }
+
+       template <class Ctx, class T, class C>
+       registered_class_options & print_func(void (T::*f)(const C &, unsigned))
+       {
+               set_print_func(Ctx::reg_info.options.get_id(), f);
+               return *this;
+       }
+
+       template <class Ctx>
+       registered_class_options & print_func(const print_functor & f)
+       {
+               set_print_func(Ctx::reg_info.options.get_id(), f);
+               return *this;
+       }

 
 private:
 
 private:

+       void set_print_func(unsigned id, const print_functor & f)
+       {
+               if (id >= print_dispatch_table.size())
+                       print_dispatch_table.resize(id + 1);
+               print_dispatch_table[id] = f;
+       }
+

        const char *name;         /**< Class name. */
        const char *parent_name;  /**< Name of superclass. */
        unsigned tinfo_key;       /**< TINFO_* key. */
        unarch_func unarchive;    /**< Pointer to unarchiving function. */
        const char *name;         /**< Class name. */
        const char *parent_name;  /**< Name of superclass. */
        unsigned tinfo_key;       /**< TINFO_* key. */
        unarch_func unarchive;    /**< Pointer to unarchiving function. */

+       std::vector<print_functor> print_dispatch_table; /**< Method table for print() dispatch */

 };
 
 typedef class_info<registered_class_options> registered_class_info;
 };
 
 typedef class_info<registered_class_options> registered_class_info;