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all_vars                                                        (Term)
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all_vars : term -> term list

SYNOPSIS
Returns the set of all variables in a term.

KEYWORDS
variable, term.

DESCRIBE
An invocation {all_vars tm} returns a list representing the set of
all bound and free term variables occurring in {tm}.

FAILURE
Never fails.

EXAMPLE

- all_vars ``!x y. x /\ y /\ y ==> z``;
> val it = [``z``, ``y``, ``x``] : term list




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

SEEALSO
Term.all_atoms, Term.all_varsl, Term.free_vars.

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