[metapost] Beginners question

[Laurence.Finston at gmx.net]

> q := p * t;

This wouldn't be valid MF or MP either.  It would have to `p transformed t', as you may know.  This would be the corresponding valid
MF or MP code:

transform t;
t = identity scaled 2.5;
pair p, q;
p = (1, 3);
q = p transformed t;
end

I don't think MF provides a tracing command that will show the parser rules as they shift and reduce (more jargon), but I could be wrong.