syntax

( defdata nametype)

type = singleton

| simple-type

| (enum lst-expr)

| (oneof typetype)

| (range numeric-typerange-constraints)

| (list type...)

| (cons typetype)

| (listof type)

| (record (field-name. type)...)

simple-type = all

| boolean

| symbol

| string

| tl

| numeric-type

numeric-type = rational

| integer

| nat

| pos

range-constraints = (num-exprlt_ltnum-expr)

| (num-exprlt_)

| (_ltnum-expr)

lt = <

| <=

> (defdata one1)

> (onep1)

t

> (defdata natlist(listof nat ))

> (natlistpnil )

t

> (natlistp(list 2358))

t

> (natlistp(list 23-58))

nil

type

( enum lst-expr)

> (defdata traffic-light(enum (list 'red'yellow'green)))

> (traffic-lightp'red)

t

> (traffic-lightp'green)

t

> (traffic-lightp'blue)

nil

type

( oneof type...)

> (defdata intstr(oneof integer string ))

> (intstrp5)

t

> (intstrp-2)

t

> (intstrp"oconto")

t

> (intstrp'watermelon)

nil

> (intstrp"watermelon")

t

> (defdata spiral(oneof nil (cons spiralspiral)))

> (spiralpnil )

t

> (spiralp(cons nil nil ))

t

> (spiralp(cons (cons nil (cons nil nil ))nil ))

t

> (spiralp(cons (cons (cons nil (cons nil nil ))

(cons (cons nil nil )nil ))

(cons nil

(cons (cons nil (cons nil nil ))nil ))))

t

> (spiralp(cons (cons nil (cons "watermelon"nil ))nil ))

nil

type

( range numeric-typerange-constraints)

numeric-type = rational

| integer

| nat

| pos

range-constraints = (num-exprlt_ltnum-expr)

| (num-exprlt_)

| (_ltnum-expr)

lt = <

| <=

> (defdata probability(range rational(0<= _<= 1)))

> (probabilityp1/2)

t

> (probabilityp2)

nil

> (probabilityp0)

t

> (probabilityp1)

t

> (defdata big-nat(range integer(24601< _)))

> (big-natp4)

nil

> (big-natp3827)

nil

> (big-natp13372462)

t

type

( record (field-name. type)...)

> (defdata fullname

(record (first . string )(last. string )))

> (defconst *x*(fullname"David""Smith"))

> *x*

(fullname "David" "Smith")

> (fullnamep*x*)

t

> (fullnamep"David")

nil

> (fullname-first*x*)

"David"

> (fullname-last*x*)

"Smith"

> (equal *x*(fullname"David""Smith"))

t