Software Requirements Specification

Parser Symbol Table for CDT 2.0

Document History

Document Version	Author	Date	Description
0.1	Andrew Niefer	12/01/03	Initial Draft
0.2	Andrew Niefer	01/09/04	Restructure & incorporate comments
0.3	Andrew Niefer	01/12/04	Add template requirements

Overview

The Parser Symbol Table provides semantic knowledge of C and C++ to the parser. It provides the ability to look up names and determine which symbol they refer to in a given context.

Clients

The symbol table has no direct impact on the end user. The parser is the only direct client of the symbol table. The symbol table will affect the performance of other features like content assist, search, and indexing.

Requirements

The following are the requirements for the symbol table in 2.0:

General Requirements

The symbol table interface must be cleaned up and made more robust.
Exceptions thrown by the symbol table must be well defined so that error handling can be improved
Traceability should be added to the symbol table to assist with debugging
Code cleanup. Much of the symbol table code has been modified many times. Code should be reviewed with an eye for efficiency and legibility.

Parser Support

The parser is the only direct client of the symbol table. Its needs are paramount.

The symbol table must support GNU language extensions as accepted by the parser. (http://gcc.gnu.org/onlinedocs/gcc-3.3.2/gcc/)
The symbol table must provide iterators over its contents so that parser clients can easily navigate the AST nodes.
Performance. The symbol table must provide its results as quickly as possible, as well as remain flexible enough to support any caching and optimization strategies employed by the parser.

Content Assist Support

In order to support Content Assist, the following requirements must be met:

The symbol table must provide a prefix lookup mode that returns all symbols with the given prefix that are visible from a given point. We must be capable of filtering the results based on type.
The symbol table must provide the ability to determine if a symbol is accessible. This requires the symbol table to properly handle friendship.
Performance. Content assist is run often, so the prefix lookup and visibility calculations must not take more time than strictly necessary.

Search Support

For the best search results, the symbol table needs to handle more of the C/C++ language:

Resolving overloaded function names without arguments is possible in certain contexts. To correctly report the references to search, the symbol table will need to provide a special lookup mode to correctly handle these cases.
C language support. Some scoping rules in C are different from C++, this needs to be handled properly. The symbol table also needs to support additional basic types ( _Complex & _Imaginary ) as well as labels.

Globalization Support

The symbol table must support unicode escape sequences within identifiers.

Template Support

The Symol table must:

support declaring, defining and instantiating templates.
support specializations and partial specializations of templates
perform template argument deduction to support implicit instantiation
perform partial ordering of template specializations to support correct cross referencing.