#lang racket
(provide make-t-modern t-modern-name t-modern-pop t-modern?
make-t-ancient t-ancient-name t-ancient-age t-ancient-left
t-ancient-right t-ancient?
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human chimp rat chicken worm fruit-fly
primate mammal vertebrate invertebrate animal)
;; THIS FILE IS A TEACHPACK. DO NOT COPY THESE DEFINITIONS INTO
;; YOUR ASSIGNMENT. INSTALL THIS TEACHPACK BY FOLLOWING THESE INSTRUCTIONS
;; 1) Save this teachpack on your computer.
;; 2) In Dr. Racket, go to Language > Add Teachpack.
;; 3) Click “Add Teachpack to List” at the bottom right.
;; 4) Chose the taxon.rkt teachpack. The teachpack will be added to the “User-installed Teachpacks” list.
;; 5) Click taxon.rkt in the list, and click OK.
;; 6) Run your program. In the interactions window, it should say “Teachpack: taxon.rkt”
;; A taxon is a t-modern or a t-ancient.
(define-struct t-modern (name pop) #:transparent)
(define-struct t-ancient (name age left right) #:transparent)
;; A t-modern is a structure (make-t-modern n p), where
;; n is a string (name of species), and
;; p is a nat (current population).
;; A t-ancient is a structure (make-t-ancient n a l r), where
;; n is a string (name of species),
;; a is a nat (in millions of years), and
;; l and r are taxons.
;; Sample data
(define human (make-t-modern “Homo Sapiens” 6500000000))
(define chimp (make-t-modern “Pan Troglodytes” 100000))
(define rat (make-t-modern ” ” 1000000000))
(define chicken (make-t-modern ” ” 15000000000))
(define worm (make-t-modern ” ” 50000000000))
(define fruit-fly (make-t-modern ” ” 100000000000))
(define primate (make-t-ancient “Primate” 5 human chimp))
(define mammal (make-t-ancient “Mammal” 65 primate rat))
(define vertebrate (make-t-ancient “Vertebrate” 320 mammal chicken))
(define invertebrate (make-t-ancient “Invertebrate” 530 worm fruit-fly))
(define animal (make-t-ancient “Animal” 535 vertebrate invertebrate))
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