Question

I’d like to parse simple C++ typedef instructions such as

typedef Class NewNameForClass; typedef Class::InsideTypedef NewNameForTypedef; typedef TemplateClass<Arg1,Arg2> AliasForObject; 

I have written the corresponding grammar that i’d like to see used in parsing.

Name <- ('_'|letter)('_'|letter|digit)* Type <- Name Type <- Type::Name Type <- Name Templates Templates <- '<' Type (',' Type)* '>' Instruction <- 'typedef' Type Name ';' 

Once this is parsed, all i’ll want to do is to generate xml with the same information (but layed out differently)

What is the most effective language for writing such a program ? How can you achieve this ?

EDIT : What i have come up with using Boost Spirit (it’s not perfect, but it’s good enough for me, at least for now)

   rule<> sep_p = space_p;    rule<> name_p =  (ch_p('_')|alpha_p) >> *(ch_p('_')|alpha_p|digit_p);    rule<> type_p = name_p            >> !(*sep_p >>str_p('::') >> *sep_p>> name_p)            >>  *(*sep_p >> ch_p('*') )            >> !(*sep_p >> str_p('const'))            >> !(*sep_p >> ch_p('&'));    rule<> templated_type_p = name_p >> *sep_p            >> ch_p('<') >> *sep_p            >> (*sep_p>>type_p>>*sep_p)%ch_p(',')            >> ch_p('>') >> *sep_p;     rule<> typedef_p = *sep_p                    >> str_p ('typedef')                    >> +sep_p >> (type_p|templated_type_p)                    >> +sep_p >> name_p                    >> *sep_p >> ch_p(';')  >> *sep_p;    rule<> typedef_list_p = *typedef_p; 

Answer 1

I would alter the grammar slightly

ShortName <- ('_'|letter)('_'|letter|digit)* Name <- ShortName Name <- Name::ShortName Type <- Name Type <- Name Templates Templates <- '<' Type (',' Type)* '>' Instruction <- 'typedef' Type Name ';' 

Also your grammar leaves out the following cases

1. Multiple typedef targets.
2. Pointer targets
3. Function pointers (this is by far the most difficult)

Parsing a grammar (i love the irony) is a fairly straight forward operation. If you wanted to actually use the grammar in a functional way, I would say the best bet is a lex/yacc combination.

But from your question it appears that you want to spit it out to another format. There really isn’t a language designed for this so I would say use whatever language you’re most comfortable with.

Edit

The OP asked about multiple typedef targets. It’s perfectly legally for a typedef declaration to have more than 1 target. For Example:

typedef _SomeStruct SomeStruct, *PSomeStruct 

This creates 2 typedef names.

1. SomeStruct which is equivalent to ‘struct _SomeStruct’
2. PSomeStruct which is equivalent to ‘struct _SomeStruct*’