Question

我正在尝试编写一个带有pyparsing的程序，解析所有字符串中包含特殊的单词。我写了下面的代码，但它不起作用：

from pyparsing import *
word = Word(alphas) 
sentence = OneOrMore(word)
day = Literal("day")
sentence_end_with_happy = sentence + day + sentence 
ret = sentence_end_with_happy.parseString("hi this is a nice day and everything is ok")

我试着用一个特殊的词来解析一个句子＆＃34; day＆＃34;但是在分析时它有错误...

pyparsing.ParseException：预期＆＃34; day＆＃34; （在char 42），（line：1，col：43）

Answer 1

在定义sh时使用否定前瞻;否则，word匹配word，day将使用它。

sentence

输出：

from pyparsing import *
day = Keyword("day")
word = ~day + Word(alphas)
sentence = OneOrMore(word)
sentence_end_with_happy = sentence('first') + day + sentence('last') 
ret = sentence_end_with_happy.parseString("hi this is a nice day and everything is ok")
print ret['first']
print ret['last']
print ret

Answer 2

pyparsing正在抛出异常，因为它将“day”视为句子中的单词。

在这种情况下，您可以使用python内置模块string函数。

In [85]: str1 = "hi this is a nice day and everything is ok"
In [86]: str2 = "day"
In [87]: str2_pos = str1.find(str2)
In [88]: str1_split_str2 = [mystr[:str2_pos], mystr[str2_pos:str2_pos+len(str2)], mystr[str2_pos+len(str2):]]

In [89]: str1_split_str2
Out[89]: ['hi this is a nice ', 'day', ' and everything is ok']

pyparsing：解析一个带有特殊单词的句子

2 个答案: