############################################################################
#
#	File:     noncase.icn
#
#	Subject:  Procedures for case-independent matching
#
#	Author:   Robert J. Alexander
#
#	Date:     May 2, 2001
#
############################################################################
#
#   This file is in the public domain.
#
############################################################################
#
# Kit of case-independent versions of Icon's built-in string-analysis
# procedures.
#
############################################################################

procedure c_any(c,s,i1,i2)
  return any(c_cset(c),s,i1,i2)
end

procedure c_find(s1,s2,i1,i2)
  local scanPos,endPos
  scanPos := match("",s2,i1,i2)
  endPos := many(&cset,s2,i1,i2) | scanPos
  suspend scanPos - 1 + find(map(s1),
      map((if \s2 then s2 else &subject)[scanPos:endPos]))
end

procedure c_many(c,s,i1,i2)
  return many(c_cset(c),s,i1,i2)
end

procedure c_match(s1,s2,i1,i2)
  local scanPos,endPos
  scanPos := match("",s2,i1,i2)
  endPos := scanPos + *s1
  return (map(s1) == map((if \s2 then s2 else &subject)[scanPos:endPos]),endPos)
end

procedure c_upto(c,s,i1,i2)
  suspend upto(c_cset(c),s,i1,i2)
end

procedure c_cset(c)
  static lstring,ustring
  initial {
    lstring := string(&lcase)
    ustring := string(&ucase)
  }
  return cset(map(c) || map(c,lstring,ustring))
end