用字典中的字符串替换python正则表达式

Question

I'm trying to create a file from a template file. The template has a few elements that need to be dynamically set based on user input or from a config file. The template contains instances of the regex I have in the code below. What I want to do is simply replace the word (\\w) contained in the regex with a know value from a dictionary. Below is my code:

def write_cmake_file(self):
    # pass
    with open (os.path.join(os.getcwd(), 'templates', self.template_name)) as f:
        lines = f.readlines()

    def replace_key_vals(match):
        for key, value in template_keys.iteritems():
            if key in match.string():
                return value

    regex = re.compile(r">>>>>{(\w+)}")
    for line in lines:
        line = re.sub(regex, replace_key_vals, line)

    with open(os.path.join(self.project_root, 'CMakeLists.txt'), 'w') as cmake_file:
        cmake_file.write(lines)

The python interpreter complains with TypeError: 'str' object is not callable . I'd like to know why this code doesn't work, and a way to fix it.

Answer 1

Change your code to:

regex = re.compile(r">>>>>{(\w+)}")
for line in lines:
    line = regex.sub(replace_key_vals, line)
    #      ---^---

You were compiling the regular expression and were trying to use it as a string afterwards, which won't work.

Answer 2

The following code fixed my problem:

def write_cmake_file(self):
    # pass
    with open (os.path.join(os.getcwd(), 'templates', self.template_name)) as f:
        lines = f.readlines()

    def replace_key_vals(match):
        print match.string
        for key, value in template_keys.iteritems():
            if key in match.string:
                return value

    regex = re.compile(r">>>>>{(\w+)}")
    # for line in lines:
        # line = regex.sub(replace_key_vals, line)
    lines = [regex.sub(replace_key_vals, line) for line in lines]

    with open(os.path.join(self.project_root, 'CMakeLists.txt'), 'w') as cmake_file:
        cmake_file.writelines(lines)