bound-1.0: Making de Bruijn Succ Less
We represent the target language itself as an ideal monad supplied by the
user, and provide a
Scope monad transformer for introducing bound variables
in user supplied terms. Users supply a
and we traverse to find free variables, and use the Monad to perform
substitution that avoids bound variables.
Slides describing and motivating this approach to name binding are available online at:
The goal of this package is to make it as easy as possible to deal with name binding without forcing an awkward monadic style on the user.
With generalized de Bruijn term you can
lift whole trees instead of just
succ to individual variables, weakening the all variables bound
by a scope and greatly speeding up instantiation. By giving binders more
structure we permit easy simultaneous substitution and further speed up