Turbo Prolog

A WORD GUESSING GAME USING WINDOWS
Program 29 uses Turbo Prolog's window facilities to produce a word guessing game. To
keep it fairly short, the operation of the program is quite primitive, but the windows
make its on-screen presentation impressive nevertheless.
The player must guess a total of three words in turn. First. s/he is asked to type in a
letter. If that letter is in the word, it is put in the YES window. If not. the letter goes into
the NO window. After each guess at a letter, the player is asked to guess the whole
word, which must then be typed in letter-by-Ietter, and the IE) key pressed after
every letter. A record is kept of the total number of guesses.
86
1* Program 29 *1
dOlains
list=symbol*
. scores=integer
predicates
member(symbol,list)
run
continue(list,scores)
yes_no_count(symbol,list)
guess_word(scores,list)
word(list,integer)
read_as_list(list,integer)
goal
makewindow(1,7,D,III1,D,D,2S,8D),
makewindow(2,7,13S,IICounting ll ,1,2D,L;,3L;),
makewindow(3,112,112,IIYES II ,S,S,7,30),
makewindow(L;,112,112,IINO II ,S,L;D,7,3D),
makewindow(S,7,7,III1,M,2D,1D,3L;),
run.
clauses
run:- word(W,L),
shiftwindow(1),clearwindow,
write(IIThe word has II,L,II lettersll ),
shiftwindow(2),clearwindow,
shiftwindow(3),clearwindow,
shiftwindow(L;),continue(W,O),fail.
continue(L,R):shiftwindow(L;),clearwindow,
write(IIGuess a letter :11),
Total=R+1,readln(T),yes_no_count(T,L),
shiftwindow(L;),clearwindow,
guess_word(Total,L),continue(L,Total).
yes_no_count(X,List):member(X,List),shiftwindow(2),write(X),!.yes_no_count(X,_):shiftwindow(3),write(X).guess_word(Count,Word):write(IIKnow
the word yet? Press y or nil),
readchar(A),A='y',cursor(O,D),
write(IIType it in one letter per line \nll),
word(Word,L),read_as_list(G,L),
G=Word,clearwindow,window_attr(112),
write(IIRight! You used II,Count,1I guess(es)II),
readchar(_),window_attr(7),!,fail.
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