DeRocket: Define 2 different test cases of expression

#lang eopl (define-datatype bintree bintree? (leaf-node (datum number?) (interior-node (key symbol?) (lelf bintree?) (right bintree?) : test case i (define mytreel (interior-node "biz (interior-node 'foo (leaf-node 2) (leaf-node 3)) (interior-node 'bar (leaf-node 4) (leaf-node 5))) (define leaf-sum (lambda (tree) (cases bintree tree (leaf-node (datum) datum) (interior-node (key left right) +(leaf-sum left) (leaf-sum right) ) #lang eopl (define-datatype bintree bintree? (leaf-node (datum number?) (interior-node (key symbol?) (lelf bintree?) (right bintree?) : test case i (define mytreel (interior-node "biz (interior-node 'foo (leaf-node 2) (leaf-node 3)) (interior-node 'bar (leaf-node 4) (leaf-node 5))) (define leaf-sum (lambda (tree) (cases bintree tree (leaf-node (datum) datum) (interior-node (key left right) +(leaf-sum left) (leaf-sum right) )