type_varsl : hol_type list -> hol_type list
STRUCTURE
SYNOPSIS
Returns the set of type variables in a list of types.
DESCRIPTION
An invocation type_varsl [ty1,...,tyn] returns a list representing the set-theoretic union of the type variables occurring in ty1,...,tyn.
FAILURE
Never fails.
EXAMPLE
- type_varsl [alpha, beta, bool, ((alpha --> beta) --> bool --> beta)];
> val it = [`:'a`, `:'b`] : hol_type list

COMMENTS
Code should not depend on how elements are arranged in the result of type_varsl.
SEEALSO
HOL  Kananaskis-13