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From: nowlin@isidev.UUCP
Newsgroups: comp.lang.icon
Subject: Re: terrible code (3)
Message-ID: <9103181658.AA05469@uunet.uu.net>
Date: 18 Mar 91 16:58:07 GMT
Sender: daemon@ucbvax.BERKELEY.EDU
Distribution: inet
Organization: The Internet
Lines: 59

Last time...promise.  I just forgot to use the 'i' and 'j' arguments in my
solution and thought as long as I'm posting it again why not comment it
some since it is a little cryptic:

procedure main(args)

	s := "that begins this string"

	l := ["th","that beg","not close","","tha","begins t","that b","t"]

	write(longstr(l,s)) | write("nomatch")
	write(longstr(l,s,6)) | write("nomatch")
	write(longstr(l,s,6,12)) | write("nomatch")

	l := ["th","that beg","not close","tha","begins t","that b","t"]

	write(longstr(l,s)) | write("nomatch")
	write(longstr(l,s,6)) | write("nomatch")
	write(longstr(l,s,6,12)) | write("nomatch")

end

procedure longstr(l,s,i,j)
    ##### borrowed #####
    /s := &subject
    if \i then {
	if i < 1 then
	    i := *s + (i+1)
    }
    else i := \&pos | 1
    if \j then {
	if j < 1 then
	    j := *s + (j+1)
    }
    else j := *s+1
    ##### borrowed #####

    # initialize the match length
    m := 0

    # while there is a pattern 'p' in list 'l' that matches string 's[i:j]'
    # and that pattern 'p' is longer than the current match length 'm' reset
    # the match length 'm' to the length of pattern 'p' -- goal directed
    # evaluation in the 'while' expression is the key here
    while *(p := (s[i:j] ? =!l)) > m do m := *p

    # if no pattern matched fail
    if /p then fail

    # if a pattern matched return the position in 's' past the pattern
    else return i + m

end

+-------------------------------------------------------------------------+
|  --- ---                                                                |
|   | S |  Iconic Software, Inc.  -  Jerry Nowlin  - uunet!isidev!nowlin  |
|  --- ---                                                                |
+-------------------------------------------------------------------------+