> Also, any modern IDE already needs to parse the AST anyway to provide any half-decent inspection features. The grammars/specs of most popular languages are al

> Also, any modern IDE already needs to parse the AST anyway to provide any half-decent inspection features. The grammars/specs of most popular languages are also readily available and well-maintained. But do those IDEs actually execute the in-language generators? Which AST are they reporting, the preprocessed or postprocessed? I've heavily used M4 with C code before and what I liked was the ability to see and run tools against the postprocessed code. Textual replacement can be thought of as a worse is better approach, a principle behind many of the systems that people enjoy and even find to be elegant (at least as long as they don't look too closely).