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exists_tyvar                                                    (Type)
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exists_tyvar : (hol_type -> bool) -> hol_type -> bool

SYNOPSIS
Checks if a type variable satisfying a given condition exists in a type.

KEYWORDS
variable, type.

DESCRIBE
An invocation {exists_tyvar P ty} searches {ty} for a type variable
satisfying the predicate {P}. The value {true} is returned if the search
is successful; otherwise {false} is the result.

FAILURE
If {P} fails when applied to a type variable encountered
in the course of searching {ty}.

EXAMPLE

- exists_tyvar (equal beta) (alpha --> beta --> bool);
> val it = true : bool




COMMENTS
This function is more efficient, in some cases, than {exists P o type_vars}.

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