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CONST Statement Programming Example
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'This example uses the CONST statement to declare symbolic constants
'for the ASCII values of nonprinting characters such as tab and
'line feed. Constants also make programs easier to modify.
'Note: You must supply a text file when you run this example.
'Use a text file you have already created, create a file
'with a text editor, or specify the README.DOC text file.
'This program counts words, lines, and characters.
'A word is any sequence of nonblank characters.
DEFINT a-z
CONST BLANK = 32, ENDFILE = 26, CR = 13, LF = 10
CONST TABC = 9, YES = -1, NO = 0
CLS 'Clear screen.
'Get the file name from the command line.
FileName$=COMMAND$
IF FileName$="" THEN
INPUT "Enter input file name: ",FileName$
IF FileName$="" THEN END
END IF
OPEN FileName$ FOR INPUT AS #1
Words=0
Lines=0
Characters=0
'Set a flag to indicate you're not looking at a
'word, then get the first character from the file.
InaWord=NO
DO UNTIL EOF(1)
C=ASC(INPUT$(1,#1))
Characters=Characters+1
IF C=BLANK or C=CR or C=LF or C=TABC THEN
'If the character is a blank, carriage return,
'line feed, or tab, you're not in a word.
IF C=CR THEN Lines=Lines+1
InaWord=NO
ELSEIF InaWord=NO THEN
'The character is a printing character,
'so this is the start of a word.
'Count the word and set the flag.
InaWord=YES
Words=Words+1
END IF
LOOP
PRINT Characters, Words, Lines
END