Python项目练习之——即时标记

最新推荐文章于 2024-06-14 08:14:15 发布

yuanCruise

最新推荐文章于 2024-06-14 08:14:15 发布

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分类专栏： Python 文章标签： python html

本文链接：https://blog.youkuaiyun.com/qiu931110/article/details/76775703

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项目功能

**遍历我所定义的规则，来处理实时读进来的文本，利用condition判断当前规则，可以用来作代码高亮处理 **

模块划分

处理程序模块
过滤器模块
处理规则模块
语法分析器模块
补充模块

处理程序模块

功能：

1.提供固定的HTML标记的输出（start & end）
2.对标记输出的start end提供友好的访问接口

class Handler:
    def callback(self, prefix, name, *args):
        method = getattr(self, prefix + name, None)
        if callable(method):return method(*args)
    def start(self, name):
        self.callback('start_', name)
    def end(self, name):
        self.callback('end_', name)

    def sub(self, name):
        def substation(match):
            result =  self.callback('sub_', name, match)
            if result is 'None': match.group(0)
            return  result
        return substation
class HTMLRenderer(Handler):
    def start_document(self):
        print('<html><head><title>...</title></head><body')
    def end_document(self):
        print('</body></html>')
    def start_paragraph(self):
        print('<p>')
    def end_paragraph(self):
        print ('</p>')
    def start_heading(self):
        print ( '<h2>')
    def end_heading(self):
        print ('</h2>')
    def start_list(self):
        print ('<ul>')
    def end_list(self):
        print ('</ul>')
    def start_listitem(self):
        print ('<li>')
    def end_listitem(self):
        print ('</li>')
    def start_title(self):
        print ('<h1>')
    def end_title(self):
        print ( '</h1>')

    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))

    def feed(self, data):
        print(data)


if __name__ == '__main__':
    callable(callable)

过滤器模块

功能：

由正则表达式组成的过滤器
1.强调过滤器（用×号标出的）
2.url过滤器
3.email过滤器

self.addFilter(r'\*(.+?)\*', 'emphasis')
self.addFilter(r'(http://[\.a-z0-9A-Z/]+)', 'url')
self.addFilter(r'([\.a-zA-Z]+@[\.a-zA-Z]+[a-zA-Z]+)','mail')

处理规则模块

功能：

主要有两个方法，condition & action
condition：用来判断读入的字符串是否符合我们的规则
action：用来执行，调用处理程序模块，输出前标签，内容，后标签

class Rule:
    def action(self, block, handler):
        handler.start(self.type)
        handler.feed(block)
        handler.end(self.type)
        return True

class HeadingRule(Rule):
    type = 'heading'
    def condition(self, block):
        return not '\n' in block and len(block) <= 70 and not  block[-1] == ':'

class TitleRule(HeadingRule):
    type = 'title'
    first = True
    def condition(self, block):
        if not self.first: return  False
        self.first = False
        return HeadingRule.condition(self, block)

class ListItemRule(Rule):
    type = 'listitem'
    def condition(self, block):
        return block[0] == '-'
    def action(self, block, handler):
        handler.start(self.type)
        handler.feed(block[1:].strip())
        handler.end(self.type)
        return True
class ListRule(ListItemRule):
    type = 'list'
    inside = False
    def condition(self, block):
        return True
    def action(self,block, handler):
        if not self.inside and ListItemRule.condition(self,block):
            handler.start(self.type)
            self.inside = True
        elif self.inside and not ListItemRule.condition(self,block):
            handler.end(self.type)
            self.inside = False
        return False

class ParagraphRule(Rule):
    type = 'paragraph'
    def condition(self, block):
        return True

语法分析器模块

功能：

协调读入的文本和其他模块的关系，提供了两个存放规则和过滤器的列表，使得规则和过滤器可以动态改变。

import sys, re
from Handler import *
from uilts import *
from rules import *

class Parser:
    def __init__(self,handler):
        self.handler = handler
        self.rules = []
        self.filters = []

    def addRule(self, rule):
        self.rules.append(rule)

    def addFilter(self,pattern,name):
        def filter(block, handler):
            return re.sub(pattern, handler.sub(name),block)
        self.filters.append(filter)

    def parse(self, file):
        self.handler.start('document')
        for block in blocks(file):
            for filter in self.filters:
                block = filter(block, self.handler)
            for rule in self.rules:
                if rule.condition(block):
                    last = rule.action(block, self.handler)
                    if last:break
        self.handler.end('document')

class BasicTextParser(Parser):
    def __init__(self,handler):
        Parser.__init__(self,handler)
        self.addRule(ListRule())
        self.addRule(ListItemRule())
        self.addRule(TitleRule())
        self.addRule(HeadingRule())
        self.addRule(ParagraphRule())

        self.addFilter(r'\*(.+?)\*', 'emphasis')
        self.addFilter(r'(http://[\.a-z0-9A-Z/]+)', 'url')
        self.addFilter(r'([\.a-zA-Z]+@[\.a-zA-Z]+[a-zA-Z]+)','mail')

handler = HTMLRenderer()
parser = BasicTextParser(handler)

parser.parse(sys.stdin)

补充模块

def line(file):
    for line in file:yield line
    yield '\n'

def blocks(file):
    block = []
    for line in file:
        if line.strip():
            block.append(line)
        elif block:
            yield ''.join(block).strip()
            block = []