Module Sstt.Transform

transform f ty returns the type obtained by applying f on the full descriptor of ty, and on the full descriptor of every node in the result recursively. It uses a cache to avoid calling f twice on the same descriptor.

Note that the function will may not terminate if f creates arbitrarily many new descriptors. For instance, if f is the function that maps singleton intervals to their successors:

    \texttt{f : } (n\texttt{..}n)\mapsto (n+1\texttt{..}n+1)
    

then when applied to a type t\equiv\texttt{(0..0)}, transform f t will not terminate.

simplify ty returns a type equivalent to ty but where atoms of all components have been merged together when possible.