Exsubst.ExSubstSourceThis modules implements extended substitution of DB variables in a term. This is typically used to: 1) infer a "most general" typing substitution from constraints gathered while inferring the type of the LHS of a rule. 2) apply the substitution to the RHS of the rule before typechecking it.
add sigma n t returns the substitution sigma with the extra mapping n -> t.
apply sigma n t applies the subsitution sigma to t considered under n lambda abstractions.
Same as apply, but outputting a boolean true if the term is modified by the substitution.
Special substitution function corresponding to given ExSubst.t instance sigma "in a smaller context": Assume sigma a substitution in a context Gamma = Gamma' ; Delta with |Delta|=i. Then this function represents the substitution sigma in the context Gamma'. All variables of Delta are ignored and substitutes of the variables of Gamma' are unshifted. This may therefore raise UnshiftExn in case substitutes of variables of Gamma' refers to variables of Delta.
mk_idempotent sigma successively applies sigma to its mapped terms until this operation has no effect anymore.
Prints the substitution using given naming function