<div dir="ltr">Not sure how to proceed with PLAI per <a href="http://cs.brown.edu/courses/cs173/2012/book/Introduction.html">http://cs.brown.edu/courses/cs173/2012/book/Introduction.html</a> The code seems not to run, e.g.,<div>
<br></div><div>#lang plai<br></div><div><br></div><div>(define-type MisspelledAnimal<br></div><div><div> [caml (humps : number)]</div><div> [yacc (height : number)])</div></div><div><br></div><div>actually wants to be</div>
<div><br></div><div><div>(define-type MisspelledAnimal</div><div> [caml (humps number?)]</div><div> [yacc (height number?)])</div></div><div><br></div><div>. . . at least DrRacket doesn't complain when I F5. But then I'm fresh out of guesses with</div>
<div><br></div><div><div>(define (good? [ma : MisspelledAnimal]) : boolean</div><div> (type-case MisspelledAnimal ma</div><div> [caml (humps) (>= humps 2)]</div><div> [yacc (height) (> height 2.1)]))</div></div>
<div><br></div><div>Please advise.</div><div><br></div><div>LB</div><div><br></div><div><br></div></div>