“即时标记”

来源：互联网发布：安卓手机主题软件编辑：程序博客网时间：2024/06/11 19:45
项目需求和原型设计来自于：《Python基础教程》第20章
类图：
相对于原版的代码，主要是把“Filter”的功能从Handler中独立出来了，使得功能模块更加清晰一点。
代码如下：
#encoding=utf-8#by pandaimport reclass filter():    '''为特定文本添加修饰性标签'''    patterns = {    'emphasis' : r'\*(.+?)\*',    'url' : r'(http://[\.a-zA-Z/]+)',    'mail' : r'([\.a-zA-Z]+@[\.a-zA-Z]+[a-zA-Z]+)',    }        def __init__(self, name):        self.name = name        self.pattern = self.patterns[self.name]         self.actionFunc = lambda matchobj: self.callback('sub_', name, matchobj) or matchobj.group(0)        def action(self, block):        return re.sub(self.pattern, self.actionFunc, block)        def callback(self, prefix, name, *args):        method = getattr(self, prefix+name, None)        if(callable(method)):            return method(*args)        else:            return None            def sub_emphasis(self, match):        return '<em>%s</em>' % match.group(1)                def sub_url(self, match):        return '<a href="%s">%s</a>' % (match.group(1), match.group(1))        def sub_mail(self,match):        return '<a href="mailto:%s">%s</a>' % (match.group(1), match.group(1))    class Rule():    '''为文本块添加标签'''    def __init__(self, handler):        self.handler = handler            def conditon(self,block):        self.block = block        return False        def action(self):        result = self.handler.start(self.type)        result += self.handler.feed(self.block)        result += self.handler.end(self.type)        print result        return result            class TitleRule(Rule):    """    The title is the first block in the document, provided that it is    a heading.    """    type = 'title'    first = True    def condition(self, block):        Rule.conditon(self,block)        if not self.first: return False        self.first = False        return not '\n' in block and len(block) <= 70 and not block[-1] == ':'class ParagraphRule(Rule):    """    A paragraph is simply a block that isn't covered by any of the    other rules.    """    type = 'paragraph'    def condition(self, block):        Rule.conditon(self,block)        return True    class Handler():    def callback(self, prefix, name,*args):        method = getattr(self, prefix+name, None)        if callable(method):            return method(*args)        def start(self, name):        return self.callback('start_', name)            def end(self, name):        return self.callback('end_', name)        class HTMLRenderer(Handler):    def start_document(self):        return unicode('<html><head><title>文本标记结果</title></head><body>', 'utf-8').encode('gbk')    def end_document(self):        return '</body></html>'    def start_paragraph(self):        return '<p>'    def end_paragraph(self):        return '</p>'    def start_heading(self):        return '<h2>'    def end_heading(self):        return '</h2>'    def start_list(self):        return '<ul>'    def end_list(self):        return '</ul>'    def start_listitem(self):        return '<li>'    def end_listitem(self):        return '</li>'    def start_title(self):        return '<h1>'    def end_title(self):        return '</h1>'    def feed(self,block):        return block        class Parser():    '''文本分析器'''    def __init__(self):        self.filters = []        self.rules = []        def parse(self, content):        result = []                for block in content:            block = block.strip()            if (len(block) == 0):                continue;            for filter in self.filters:                block = filter.action(block)                                for rule in self.rules:                if rule.condition(block):                    last = rule.action()                    if last:                        block = last                        break;            result.append(block)        return ''.join(result)                    def addRule(self,rule):        self.rules.append(rule)        def addFilter(self,name):        self.filters.append(filter(name))    class BasicTextParser(Parser):    def __init__(self,handler):        Parser.__init__(self)        self.handler = handler        self.addFilter('emphasis')        self.addFilter('url')        self.addFilter('mail')                self.addRule(TitleRule(handler))        self.addRule(ParagraphRule(handler))            def parse(self, content):        result = []        result.append(self.handler.start('document'))        result.append(Parser.parse(self,content))        result.append(self.handler.end('document'))        return ''.join(result)            #import sysif __name__ == '__main__':    handler = HTMLRenderer()    parser = BasicTextParser(handler)    f = open('test_input.txt')    f2 = open('test.html','w')#    p.parse(sys.stdin)    output = parser.parse(f)    print output    f2.write(output)    f2.close()    f.close()