Class Metaobjects

Public Members (cont.)


Ptree* Comments()

This returns a list of comments preceding the class declaration. If no comments are given, this function returns nil. The compiler recognizes a comment string as a single token. The comment string includes "//" or "/* */". The returned value is a list of Ptree objects each of which represents a single comment string (token).

Note: To use this function, run the compiler with the -C option.

Member Metaobjects

Public Members (cont.)


Ptree* Comments()

This returns a list of comments preceding the member declaration. If no comments are given, this function returns nil. The compiler recognizes a comment string as a single token. The comment string includes "//" or "/* */". The returned value is a list of Ptree objects each of which represents a single comment string (token).

Note: To use this function, run the compiler with the -C option.

TemplateClass Metaobjects

TemplateClass metaobjects represent template classes. It is a subclass of Class.

The metaclass for any template class must be TemplateClass or its subclass.

Public Members

Ptree* TemplateDefinition()

This returns the whole definition of the template.

Ptree* TemplateArguments()

This returns template arguments.

Ptree* TranslateInstantiation(Environment* env, Ptree* spec)

This translates a template instantiation. An example of template instantiation is:

template class Foo<int>;

Here, Foo is a template class.

--- Defualt implementation by Template
This returns spec.

C functions

Class metaobjects can be used for translating C functions.

If the compiler encounters a C function declaration, it calls TranslateMemberFunction() on the Class metaobject for C functions. The Member metaobject representing the C function is passed to that member function as an argument. All C functions are handled by a single Class metaobject.

If the compiler encounters a C function call, then it calls TranslateFunctionCall() on the Class metaobject for C functions.

To translate C functions, first define the class for the metaobject handling C functions. Then, call this member function:


static void Class::SetMetaclassForFunctions(char* name)

This registers the name of the metaclass for C functions. The compiler creates an instance of this metaclass for handling C functions. The metaclass must be a subclass of Class.

This member function must be called just after the compiler has started. For more information about when it should be called, see the description of Class::ChangeDefaultMetaclass().

Representation of Types

TypeInfo metaobjects represent types.

Public Members (cont.)


bool NthTemplateArgument(int nth, TypeInfo& t)

If the type is TemplateType, this returns the n-th (>= 0) template argument in t. If the type is not TemplateType or the n-th template argument does not exist, this function returns false.

The example program shown below prints the name and all the arguments of the given template type. Suppose that a variable tinfo is a TypeInfo metaobject representing a template type:

TypeInfo t;
tinfo.FullTypeName()->Display();
int i = 0;
while (tinfo.NthTemplateArgument(i++, t))
    t.FullTypeName()->Display();

Representation of Environments

Environment metaobjects represent bindings between names and types.

Public Members (cont.)


Ptree* GetLineNumber(Ptree* expr, int& number)

Returns the name of the file including the source text represented by expr. The line number of that text is stored in number.

Ptree* IsNamespace()

If this environment represents a name space, then this member function returns the name of that name space. Otherwise, it returns nil.