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all_varsl                                                       (Term)
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all_varsl : term list -> term list

SYNOPSIS
Returns the set of all variables in a list of terms.

KEYWORDS
variable, term.

DESCRIBE
An invocation {all_varsl [t1,...,tn]} returns a list representing
the set of all term variables occurring in {t1,...,tn}.

FAILURE
Never fails.

EXAMPLE

- all_varsl [Term `x /\ y /\ y ==> x`,
             Term `!a. a ==> p ==> y`];
> val it = [`x`, `y`, `p`, `a`] : term list




COMMENTS
Code should not depend on how elements are arranged in the
result of {all_varsl}.

SEEALSO
Term.all_atoms, Term.all_vars, Term.empty_varset, Term.free_vars_lr,
Term.free_vars, Term.free_varsl, Term.FVL, Type.type_vars.

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