Modal commands with Dragonfly

Question

I'm using dragonfly2, and I want to create a grammar that, like vim, is modal. I want to be able to enable and disable grammars using commands.

For example, if I say link, I have an action that shows a list of possible links on screen with 2-letter labels, so I want the grammar to enable a mode that only accepts 2-letter words. In particular, after saying link, I don't want the grammar to accept any normal command, like another link.

Is this possible?

Answer 1

Ah ha! I just found this in someone else's grammar:

class PythonEnabler(CompoundRule):
    spec = "Enable Python"                  # Spoken command to enable the Python grammar.

    def _process_recognition(self, node, extras):   # Callback when command is spoken.
        pythonBootstrap.disable()
        pythonGrammar.enable()
        print "Python grammar enabled"

class PythonDisabler(CompoundRule):
    spec = "switch language"                  # spoken command to disable the Python grammar.

    def _process_recognition(self, node, extras):   # Callback when command is spoken.
        pythonGrammar.disable()
        pythonBootstrap.enable()
        print "Python grammar disabled"

pythonBootstrap = Grammar("python bootstrap")                
pythonBootstrap.add_rule(PythonEnabler())
pythonBootstrap.load()

pythonGrammar = Grammar("python grammar")
pythonGrammar.add_rule(PythonTestRule())
pythonGrammar.add_rule(PythonCommentsSyntax())
pythonGrammar.add_rule(PythonControlStructures())
pythonGrammar.add_rule(PythonDisabler())

So basically, you can simply use some_grammar.disable() or some_grammar.enable!