[plt-scheme] Code generation question from Shriram's Automata via Macros

On 8/2/07, Noel Welsh <noelwelsh at gmail.com> wrote:
> On 8/2/07, Grant Rettke <grettke at acm.org> wrote:
> > Suppose I took that definition and did something like:
> >
> > (define the-data
> > "(automaton init
> >                      (init :
> >                            (c -> more))
> >                      (more :
> >                            (a -> more)
> >                            (d -> more)
> >                            (r -> end))
> >                      (end : )))"
> >
> > First question, how would I got about evaluating it and binding it to
> > a value like in previous example?
>
> http://schemecookbook.org/Cookbook/StringEval

One could use eval here, but may I ask why you've got a string in the
first place?

> > Second, how could I take the definition of 'the-data' and use that
> > language to, for example, create a graphviz file that represented the
> > state machine?
>
> Easy.  Just walk the data structure and spit out the right strings.  I
> do it all the time for POMDPs, which are kinda an extended finite
> state machine.

Given this particular code, you might try instead to write a different
implementation of the automaton macro that produces the input for dot.

Robby