Just a quick check on the highly unlikely off-chance that I'm going to waste my time if I start planning how to create one myself, has anyone seem a GUI grammar editor?

By which I mean something that presents a visual flow-chart style interface - similar to a mind-map but tailored towards grammar concepts (tokens,rules,alternation,repetition,etc)?

What I want is a quick-and-easy way to plan and restructure a grammar definition, in a visual format (similar style to images here), which can be exported as images, maybe an interactive HTML map, and of course as actual BNF/EBNF grammars.

(What I'm not looking for is a way to generate images from an existing text-based grammar, which appears to be the limit of what existing stuff does.)

And - given that I'm not expecting anyone to say "oh yeah, here's one" - does anyone have any tips on a good way to approach this?

Current plan is to rip apart this js-mindmap project and see if I can do what I want with it.

Any other ideas?

I found DiaGen which is a Diagram Editor Generator, for creating editors for specific customised types of diagrams, which sounded promising.

It even has an example of a Syntax Diagram Editor:


Which might have been good if it wasn't such a clunky piece of shite, and a stereotypical example of a unresponsive Java GUI, and lacking in basic features (like keyboard shortcuts).

Still, if I search more for "syntax diagram editor" I might actually find a better version of what I'm looking for. :)

And there was me thinking that this would be like Word's grammar checker, but actually not being a pain in the arse. :|

Heh, I guess I did forget to specify I was talking about computer language grammars.

Sorry for getting your hopes up. :(

This really is one of those times when you're better off with a good text editor (e.g. Vim) with decent syntax highlighting.