Object-Oriented	GDL allows you to derive a grammar from other grammars. Derived grammars inherit all the symbols from their parents, and may selectively override or extend them. This facilitates the creation of reusable grammars that can be extended or modified as needed.
High-Level	GDL provides high-level constructs that simplify grammar development by directly handling many parsing-related issues, such as: comparing upper and lower-case strings scanning whitespace skipping comments parsing fixed-length and variable-length tokens parsing common types of tokens, such as alpha and numeric parsing optional and repeating data elements
Programming Language-Independent	Programming language statements are not included in grammar definitions, resulting in parsers that are programming language-independent, less cluttered, and more reusable. Because GDL is language-neutral, and parsers are developed independently of the applications that use them, the same grammar can be used by all types of applications, including C++, Visual Basic, and Delphi.
Advanced Features	GDL supports a number of advanced features. Using symbol attributes, each production rule can control the behavior of the parser in a context-dependent manner. For example, the way in which whitespace is skipped can be tailored for different sections of the input. Parse constraints allow the parser to make decisions at runtime, based on the values of symbols that have already parsed. Constraints are used to resolve ambiguities, simplify certain types of grammars, and to enforce integrity rules on the parse tree as it's being built. Various error handling primitives help the parser to gracefully recover from syntax errors and to report them in a meaningful way.