#!/usr/bin/env python3 # code generated by "translate.py.pss" a pep script # bumble.sf.net/books/pars/ import sys, re # for sys.read(), write() and regex from unicodedata import category # for matching classes # may use, which could make the char class code easier # import regex # regex.findall(r'[[:graph:]]', 'a 0 a b z') class Machine: # make a new machine def __init__(self): self.size = 300 # how many elements in stack/tape/marks self.eof = False # end of stream reached? self.charsRead = 0 # how many chars already read self.linesRead = 1 # how many lines already read self.escape = "\\" self.delimiter = "*" # push/pop delimiter (default "*") self.counter = 0 # a counter for anything self.work = "" # the workspace self.stack = [] # stack for parse tokens self.cell = 0 # current tape cell self.tape = [""]*self.size # a list of attribute for tokens self.marks = [""]*self.size # marked tape cells # or dont initialse peep until "parse()" calls "setInput()" self.peep = sys.stdin.read(1) def setInput(self, newInput): print("to be implemented") # read one character from the input stream and # update the machine. def read(self): if self.eof: System.exit(0) self.charsRead += 1; # increment lines if self.peep == "\n": self.linesRead += 1 self.work += self.peep self.peep = sys.stdin.read(1) if not self.peep: self.eof = True # increment the tape pointer (command ++) and increase the # tape and marks array sizes if necessary def increment(self): self.cell += 1 if self.cell >= self.size: self.tape.append("") self.marks.append("") self.size += 1 # test if all chars in the text are in the unicode category # no! bug! because while checks mm.peep, but class test # checks mm.work. so have to adapt this function for either. def isInCategory(self, cat, text): for ch in text: if not category(ch).startswith(cat): return False return True # def # remove escape character: trivial method ? def unescapeChar(self, c): if len(self.work) > 0: self.work = self.work.replace("\\"+c, c) # add escape character : trivial def escapeChar(self, c): if len(self.work) > 0: self.work = self.work.replace(c, "\\"+c) # a helper function for the multiple escape char bug def countEscaped(self, suffix): count = 0 if self.work.endswith(suffix): # removesuffix not available in early python s = self.work.removesuffix(suffix) while s.endswith(self.escape): count += 1 s = s.removesuffix(self.escape) return count # reads the input stream until the workspace end with text def until(self, suffix): # read at least one character if self.eof: return self.read() while True: if self.eof: return # no. bug! count the trailing escape chars, odd=continue, even=stop if self.work.endswith(suffix): #and (not self.work.endswith(self.escape + suffix)): if self.countEscaped(suffix) % 2 == 0: return self.read() # pop the first token from the stack into the workspace */ def pop(self): if len(self.stack) == 0: return False self.work = mm.stack.pop() + self.work if self.cell > 0: self.cell -= 1 return True # push the first token from the workspace to the stack def push(self): # dont increment the tape pointer on an empty push if len(self.work) == 0: return False # need to get this from the delimiter. iFirst = self.work.find(self.delimiter); if iFirst == -1: self.stack.append(self.work) self.work = "" return True self.stack.append(self.work[0:iFirst+1]) self.work = self.work[iFirst+1:] self.increment() return True # this function is not used (the code is "inlined") def swap(self): s = self.work self.work = self.tape[self.cell] self.tape[self.cell] = s def goToMark(self, mark): markFound = False length = len(self.marks) for ii in range(length): if (mm.marks[ii] == mark): mm.cell = ii; markFound = True if (markFound == False): print("badmark '" + mark + "'!") exit() def writeToFile(self): f = open("sav.pp", "w") f.write(self.work) f.close() def printState(self): print("Stack[" + ",".join(self.stack) + "] Work[" + self.work + "] Peep[" + self.peep + "]"); print("Acc:" + str(self.counter) + " Esc:" + self.escape + " Delim:" + self.delimiter + " Chars:" + str(self.charsRead) + " Lines:" + str(self.linesRead) + " Cell:" + str(self.cell)); # this is where the actual parsing/compiling code should go # so that it can be used by other python classes/objects. Also # should have a stream argument. def parse(self, s): # a reset or "setinput()" method would be useful to parse a # different string/file/stream, without creating a new # machine object. # could use code like this to check if input is string or file if isinstance(s, file): print("") # self.reset(s) # self.reader = s elif isinstance(s, string): f = StringIO.StringIO("test") for line in f: print(line) else: f = sys.stdin sys.stdout.write("not implemented") # end of Machine class definition # will become: # mm.parse(sys.stdin) or # mm.parse("abcdef") or # open f; mm.parse(f) temp = "" mm = Machine() while (not mm.eof): # lex block while True: mm.read() # read # ignore \r if (re.match(r"^[\r]+$", mm.work)): mm.work = '' # clear if (mm.eof): break continue # dont tokenize non-leading space. One space will be printed # between each word. if (re.match(r"^[ \t\f]+$", mm.work)): # while while re.match(r"^[ \t\f]+$", mm.peep): if mm.eof: break mm.read() mm.work = '' # clear if (mm.eof): break continue if (re.match(r"^[\n]+$", mm.work)): # make character count relative to line. mm.charsRead = 0 # nochars # save the leading space in the nl* token # while while re.match(r"^[\s]+$", mm.peep): if mm.eof: break mm.read() mm.tape[mm.cell] = mm.work # put mm.work = '' # clear mm.work += "nl*" mm.push(); break # everything else is a word if (mm.work != ""): # whilenot while not re.match(r"^[\s]+$", mm.peep): if mm.eof: break mm.read() mm.tape[mm.cell] = mm.work # put mm.work = '' # clear mm.work += "word*" mm.push(); break break # parse block while True: # to visualise parse token reductions mm.work += "line " mm.work += str(mm.linesRead) # lines mm.work += " char " mm.work += str(mm.charsRead) # chars mm.work += ": " sys.stdout.write(mm.work) # print mm.work = '' # clear while (mm.pop()): continue # unstack mm.work += "\n" sys.stdout.write(mm.work) # print # if len(mm.work) > 0: # clip mm.work = mm.work[:-1] # clip while (mm.push()): continue # stack #------- # 1 token mm.pop(); #------- # 2 tokens mm.pop(); # I want to recognise 2 word structures, so need to separate # the text*word* reduction from the word*word* rule. # is there any need for a file* token, link token etc? if (mm.work == "word*word*" or mm.work == "text*word*"): mm.work = '' # clear mm.work += mm.tape[mm.cell] # get mm.work += " " mm.increment() # ++ mm.work += mm.tape[mm.cell] # get if mm.cell > 0: mm.cell -= 1 # -- mm.tape[mm.cell] = mm.work # put mm.work = '' # clear mm.work += "text*" mm.push(); continue if (mm.work == "word*nl*" or mm.work == "text*nl*"): mm.work = '' # clear mm.work += mm.tape[mm.cell] # get mm.increment() # ++ mm.work += mm.tape[mm.cell] # get if mm.cell > 0: mm.cell -= 1 # -- mm.tape[mm.cell] = mm.work # put mm.work = '' # clear mm.work += "line*" mm.push(); continue if (mm.work == "line*line*" or mm.work == "lineset*line*"): mm.work = '' # clear mm.work += mm.tape[mm.cell] # get mm.increment() # ++ mm.work += mm.tape[mm.cell] # get if mm.cell > 0: mm.cell -= 1 # -- mm.tape[mm.cell] = mm.work # put mm.work = '' # clear mm.work += "lineset*" mm.push(); continue mm.push(); mm.push(); if (mm.eof): mm.pop(); if (mm.work == "word*" or mm.work == "text*" or mm.work == "line*" or mm.work == "lineset*"): mm.work = '' # clear mm.work += mm.tape[mm.cell] # get mm.work += "\n" sys.stdout.write(mm.work) # print mm.work = '' # clear exit() break # parse # end of code generated by tr/translate.py.pss