Sha256: a2792157d41221eefa0ccdbd7f624b23360517b4b96df108d6348fa73a45e087
Contents?: true
Size: 674 Bytes
Versions: 17
Compression:
Stored size: 674 Bytes
Contents
(declare empty-stack [A --> [stack B]])
(declare push [A --> [stack A] --> [stack A]])
(declare top [[stack A] --> A])
(declare pop [[stack A] --> [stack A]])
(define empty-stack
_ -> (/. X (if (or (= X pop) (= X top))
(error "this stack is empty~%")
(error "~A is not an operation on stacks.~%" X))))
(define push
X S -> (/. Y (if (= Y pop)
S
(if (= Y top)
X
(error "~A is not an operation on stacks.~%" Y)))))
(define top
S -> (S top))
(define pop
S -> (S pop))
Version data entries
17 entries across 17 versions & 1 rubygems