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dom_rng                                                         (Type)
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dom_rng : hol_type -> hol_type * hol_type

SYNOPSIS
Breaks a function type into domain and range types.

KEYWORDS
type

DESCRIBE
If {ty} has the form {ty1 -> ty2}, then {dom_rng ty} yields {(ty1,ty2)}.

FAILURE
Fails if {ty} is not a function type.

EXAMPLE

- dom_rng (bool --> alpha);
> val it = (`:bool`, `:'a`) : hol_type * hol_type

- try dom_rng bool;

Exception raised at Type.dom_rng:
not a function type




SEEALSO
Type.-->, Type.dest_type, Type.dest_thy_type.

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