CS 131

Homework Template and Design Recipe Template
Version as of 10-11-02

at the beginning of the homework file:
;***********************************************************
; type in your name (or both names, IF working as a pair)
; CS 131 HW X
; last modified:
;***********************************************************

...for each problem on the homework:
;***********************************************************
; Problem X
;

Order of design recipe steps:

 data analysis and definition (including data definitions, IF needed)
 contract, header, and purpose statement
 template (IF needed)
 examples
 body
 tests



function "template" for easier cut-and-paste:
;;----------------------------------------------------------
;; a x is a structure:
;;    (make-x y1 y2 ... yn)
;; ...where y1 is a dt, y2 is a dt, ...
;; and yn is a dt.
;; THEN, add a brief sentence EXPLAINING x's meaning.

(define-struct x (y1 y2 ... yn))
;;----------------------------------------------------------
;; a y is either:
;;    1. a x structure, or
;;    2. a y structure, or 
;;    ...
;;    n. a z structure.
;;    (note: assuming that data definitions for x-z have been given)
;;    THEN, add a a brief sentence EXPLAINING y's meaning, if not obvious.
;;----------------------------------------------------------
;; a list-of-type is either:
;;    1. the empty list, empty, or
;;    2. (cons type-inst type-list)
;;       ...where type-inst is a type and type-list is a
;;       list-of-type.
;;    THEN, add a brief sentence EXPLAINING list-of-type's meaning, if not obvious.
;;----------------------------------------------------------

;; CONTRACT: 

;; PURPOSE: 

;; EXAMPLES:

;; (note: modify template as appropriate to include cond's, selectors, list operators, etc.)
;; TEMPLATE:
;; (define (process-x a-x)
;; ... (x-y1 a-x) ...
;; ... (x-y2 a-x) ...
;; ...
;; ... (x-yn a-x) ...)

(define 
   ; expr to go here
) 

;; TESTS:
;;---------------------------------------------------------------------------

 function "template" with more explanation:
...to be done for EACH function (auxiliary OR main):
;;-----------------------------------------------------------
;; (ONLY IF APPROPRIATE FOR PROBLEM; note that a data definition used for
;; several functions within a program only needs to appear ONCE,
;; before the first function using that compound data.)
;; DATA ANALYSIS and DEFINITIONS:
;; (include a data definition for EACH structure needed) 
;------------------------------------------------------------
;; a mystruct is a structure:
;;     (make-mystruct x1 x2 ... xn)
;; ...where x1 is a x1-datatype, x2 is a x2-datatype, ...
;; and xn is a xn-datatype.
;; THEN, add a brief sentence EXPLAINING mystruct's meaning. 

(define-struct mystruct (x1 x2 ... xn))

;; note that the following supertype definition is assumed to be preceded
;; by data definitions of all of the subtypes x-z that it uses.
;-----------------------------------------------------------
;; a supertype is either:
;;    1. a x structure, or
;;    2. a y structure, or 
;;    ...
;;    n. a z structure.
;;    THEN, add a a brief sentence EXPLAINING supertype's meaning, if not obvious.
;;----------------------------------------------------------
;; a list-of-type is either:
;;    1. the empty list, empty, or
;;    2. (cons type-inst type-list)
;;       ...where type-inst is a type and type-list is a
;;       list-of-type.
;;    THEN, add a brief sentence EXPLAINING list-of-type's meaning, if not obvious.
;;----------------------------------------------------------

;; CONTRACT: function-name : input types -> output types

;; PURPOSE: type in PURPOSE STATEMENT for function-name, making
;; use of parameter names from header/definition

;; EXAMPLES:
;; (function-name specific-arguments) should produce actual-value
;;    (how many examples? We'll refine this --- but, for now, try to 
;;    have one for each main "category" of data that might occur,
;;    plus "boundary" situations.)

;; (note: modify template as appropriate to include cond's, selectors, list operators, etc.)
;; TEMPLATE:
;; (define (process-mystruct a-mystruct)
;; ... (mystruct-x1 a-mystruct) ...
;; ... (mystruct-x2 a-mystruct) ...
;; ...
;; ... (mystruct-xn a-mystruct) ...)

(define (function-name parameter-names)
   ; expr for function-name's body, indented. BUT final parenth can be here: )
) ; ...or here.

;; TESTS:
; type in your specific tests (from examples above) here. 
; you may choose to compare your function call result to your expected 
; result, as in:
(= (function-name actual-arguments)
   expected-result)
; or, you may type so both will show on consecutive lines:
(function-name actual-arguments)
; expected result
expected-result
; (and these two styles may be mixed and matched as needed, as long
; as all examples are actually run as tests)
;;-----------------------------------------------------------

 data definition examples:
;------------------------------------------------------------
; general structure of a DATA DEFINITION:
;------------------------------------------------------------
;; a my-new-struct is a structure:
;;     (make-my-new-struct info-1 info-2 ... info-n)
;; ...where info-1 is a data-type and info-2 is a data-type ... 
;; and info-n is a data-type
;; THEN, add a brief sentence EXPLAINING my-new-struct's meaning.

;(define-struct my-new-struct (info-1 info-2 ... info-n))
;------------------------------------------------------------

; for example,
;------------------------------------------------------------
;; a prof is a structure:
;;     (make-prof name office-hours office-num email)
;; ...where name, office-hours, office-num, and email are symbols.
;; prof represents a professor at Fictional State University.

(define-struct prof (name office-num office-hours email))
;------------------------------------------------------------