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The variable bst is something that can be matched with Empty and with Node(item, left, right), both of which are of type BST. When two values can be matched wit
by omaranto 9y ago
The variable bst is something that can be matched with Empty and with Node(item, left, right), both of which are of type BST. When two values can be matched with each other, they must be of the same type. Therefore bst is of type BST too.