Labels:text | screenshot | menu | font OCR: -- Our solution to Outside Assignment 5: with TEXT_I0; use TEXT_IO; procedure LEDIT is MAXLENGTH constant := 80; MAX_LINE_NUMBER: constant := 29_999; type TEA TEXT is record LEN: INTEGER range 0.. MAX_LENGTH = 0; VAL: STRING(1 MAX_LENGTH); end record; type LINK: type P is access LINK: type LINK is record NUM : POSITIVE; LINE : TEXT; NEXT : P: end record; HEAD : P = new LINK; : P; TEMP : FILE_TYPE: INPUT_FILE OUTPUT_FILE : FILE_TYPE; : TEXT: INPUT FINISHED LINE_NUM : BOOLEAN := FALSE; : NATURAL := 10; function STRCT in TEXT) return STRING is separate: procedure READ_INPUT_FILE is separate; procedure DO COMMAND is separate: begin PUT("Input file: "); GET_LINE(INPUT.VAL, INPUT.LEN); READ_INPUT FILE; PUT("Output file: "); GET_LINE(INPUT.VAL, INPUT.LEN); CREATE (OUTPUT_FILE, NAME => STR(INPUT)); -- Get and process commands. while not FINISHED loop PUT("> "); _GET_LINE(INPUT.VAL, INPUT. LEN); DO_COMMAND; end loop; - Write the output file. TEMP = HEAD.NEXT; Skip unused link at start of linked list. while TEMP/= null loop PUT_LINE(OUTPUT_FILE, STR (TEMP.LINE)); -- Write line of text. TEMP = TEMP. NEXT; -- Get next link. end loop; CLOSE (OUTPUT_FILE); end LEDIT: 9 separate (LEDIT) function STR(T in TEXT) return STRING is begin return T.VAL(1 .. T.LEN); end STR: separate (LEDIT) procedure READ_INPUT_FILE is begin If the input file exists, display a message and read it in. OPEN (INPUT_FILE, IN_FILE, STR(INPUT)); PUT_LINE("File found."); TEMP := HEAD: while not END_OF_FILE(INPUT_FILE) loop -- Read a line. GET_LINE(INPUT_FILE, INPUT.VAL, INPUT.LEN); TEMP.NEXT = new LINK' (LINE_NUM, INPUT, null); -- Add to list. -- Advance pointer to next link. TEMP = TEMP. NEXT: LINE_NUM= LINE_NUM + 10; end loop; CLOSE(INPUT_FILE); exception If the input file doesn't exist, just display a message. when NAME_ERROR => PUT_LINE("File not found."); end READ_INPUT_FILE; separate (LEDIT) procedure DO COMMAND is procedure DELETE_FIRST_CHARACTERCT in out TEXT) is separate: procedure GET_LEADING_INTEGER (N out NATURAL) is separate: procedure STRIP_LEADING_SPACES_FROM_INPUT is separate; procedure ADD_DELETE_REPLACE_LINE is separate: procedure LIST is separate: begin STRIP LEADING_SPACES_FROM_INPUT; if STR(INPUT) = "exit" or STR(INPUT) = "EXIT" then FINISHED := TRUE; elsif INPUT. LEN >= 4 and (INPUT.VAL(1 .. 4) = "list" or INPUT.VAL(1 .. 4) = "LIST") then LIST; elsif INPUT. LEN > 0 and INPUT.VAL(1) not in '0'.. '9' then PUT_LINE("Unrecognized command."); elsif INPUT. LEN > 0 then GET_LEADING_INTEGER (LINE_NUM); if LINE_NUM not in 1.. MAX_LINE_NUMBER then PUT_LINE("Illegal line number."); else ADD_DELETE_REPLACE_LINE; end if; exception when NUMERIC_ERROR I CONSTRAINT_ERROR => PUT_LINE("Line number too large."); end DO COMMAND; Į separate (LEDIT.DO_COMMAND) procedure ADD_DELETE_REPLACE_LINE is INP : TEXT := INPUT; begin then -- Treat "9x" like "9 x". if INP.LEN > 0 and INP.VAL(1) = ' DELETE_FIRST_CHARACTER(INP); end if; TEMP := HEAD; -- Find where this number belongs in linked list. while TEMP /= null and then TEMP.NEXT = null and then TEMP.NEXT.NUM <= LINE_NUM loop if TEMP.NEXT.NUM = LINE_NUM then TEMP.NEXT := TEMP.NEXT.NEXT; -- Delete line. -- Advance to next link in list. else TEMP = TEMP. NEXT; end if; end loop; if INPUT. LEN > 0 then -- Add line. TEMP. NEXT := new LINK' (LINE_NUM, INP, TEMP.NEXT); end if; end_ADD_DELETE_REPLACE_LINE: separate (LEDIT.DO_COMMAND) procedure DELETE_FIRST_CHARACTER(T in out TEXT) is begin T.VAL(1 .. T.LEN 1) = T.VAL(2 T.LEN); T.LEN := T.LEN - 1; end DELETE_FIRST_CHARACTER; separate (LEDIT.DO_COMMAND) procedure GET_LEADING_INTEGER (N out NATURAL) is ANS: INTEGER := 0; begin while INPUT. LEN > 0 and INPUT.VAL(1) in '0'.. '9' loop ANS := ANS*10+ CHARACTER' POS (INPUT.VAL(1)) -CHARACTER' POS('0'); DELETE_FIRST_CHARACTER(INPUT); end loop; N = ANS; end GET_LEADING_INTEGER; separate (LEDIT.DO_COMMAND) procedure STRIP_LEADING_SPACES_FROM_INPUT is begin while INPUT. LEN > 0 and INPUT.VAL(1) = DELETE_FIRST_CHARACTER(INPUT); end loop; loop 9 end STRIP_LEADING_SPACES_FROM_INPUT: separate (LEDIT.DO_COMMAND) procedure LIST is package II0 is new INTEGER_IO(INTEGER); use II0; START, FINISH : NATURAL: VALID : BOOLEAN := TRUE; W begi IND INPUT. LEN := INPUT.LEN – 4; -- Delete the name of the command. INPUT.VAL(1.. INPUT.LEN) == INPUT.VAL(5 .. INPUT.LEN + 4); For "LIST" alone, list all lines. -- Get number after "LIST". For "LIST n", list only line n. Else "-" must follow n. STRIP_LEADING_SPACES_FROM_INPUT; if INPUT.LEN=0 then START = 0; FINISH = MAX_LINE_NUMBER + 1; else GET_LEADING_INTEGER (START); STRIP LEADING_SPACES_FROM_INPUT; if INPUT. LEN = 0 then FINISH = START: elsif INPUT.VAL(1) /= '-' then VALID = FALSE; else DELETE_FIRST_CHARACTER(INPUT); STRIP_LEADING_SPACES_FROM_INPUT; GET_LEADING_INTEGER(FINISH); STRIP_LEADING_SPACES_FROM_INPUT; if FINISH = 0 and START = 0 then VALID = FALSE; elsif FINISH = 0 then FINISH := MAX_LINE_NUMBER + 1; end if; VALID = VALID and INPUT. LEN = 0; end if; Delete the "-". Get number after "-". "LIST -" isn't valid. For "LIST n-", list n through end. -- No trailing garbage. end if; if not VALID then PUT_LINE("Illegal syntax for LIST."); else TEMP = HEAD.NEXT; -- Skip unused link at start of linked list. while TEMP /= null and then TEMP.NUM <= FINISH loop if TEMP.NUM >= START then PUT(TEMP.NUM, WIDTH => 5); -- Display line #, width 5. PUT_LINE(' & STR(TEMP.LINE)); -- Display text of line. end if; TEMP = TEMP. NEXT; end loop: Get next link. end if; exception when NUMERIC_ERROR I CONSTRAINT_ERROR => PUT_LINE("Line number too large in LIST."); end LIST: end if;
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