CoreSubst

# Main data types

data Subst
type TvSubstEnv
type IdSubstEnv
data InScopeSet

## Substituting into expressions and related types

deShadowBinds
substTy
substExpr
substSpec
substWorker
lookupIdSubst
lookupTvSubst

## Operations on substitutions

emptySubst
mkEmptySubst
mkSubst
substInScope
isEmptySubst
extendIdSubst
extendIdSubstList
extendTvSubst
extendTvSubstList
extendSubst
extendSubstList
zapSubstEnv
extendInScope
extendInScopeList
extendInScopeIds
isInScope

## Substituting and cloning binders

substBndr
substBndrs
substRecBndrs
cloneIdBndr
cloneIdBndrs
cloneRecIdBndrs