Python markdown 模块，util() 实例源码

def resolve_url(self, url):
        """
        Resolve internal URLs.

        Returns None if the URL does not need changing, else returns the new URL.
        """
        from markdown.util import AMP_SUBSTITUTE
        if not url:
            return None
        if url.startswith(AMP_SUBSTITUTE):
            # Possibly an overencoded mailto: link.
            # see https://bugs.debian.org/816218
            #
            # Markdown then further escapes & with utils.AMP_SUBSTITUTE, so
            # we look for it here.
            return None
        parsed = urlparse(url)
        if parsed.scheme or parsed.netloc:
            return None
        if not parsed.path:
            return None
        dest = self.page.resolve_link(parsed.path)
        # Also allow .md extension in
        if dest is None and parsed.path.endswith(".md"):
            dirname, basename = os.path.split(parsed.path)
            if basename in ("index.md", "README.md"):
                dest = self.page.resolve_link(dirname)
            else:
                dest = self.page.resolve_link(parsed.path[:-3])
        if dest is None:
            log.warn("%s: internal link %r does not resolve to any site page", self.page.src_relpath, url)
            return None

        return urlunparse(
            (parsed.scheme, parsed.netloc, dest.dst_link, parsed.params, parsed.query, parsed.fragment)
        )

def run(self, parent, blocks):
        sibling = self.lastChild(parent)
        block = blocks.pop(0)

        block, theRest = self.detab(block)
        block = block.rstrip()

        block_is_html = False
        if "<div " in block or "</" in block or "<span " in block:
            block_is_html = True

        if (sibling is not None and sibling.tag == "div"):
            # The previous block was a code block. As blank lines do not start
            # new code blocks, append this block to the previous, adding back
            # linebreaks removed from the split into a list.

            block_is_html = block_is_html and not isinstance(sibling.text, AtomicString)

            block = u'\n'.join([sibling.text, block])
            output = sibling
        else:
            # This is a new codeblock. Create the elements and insert text.
            output = markdown.util.etree.SubElement(parent, 'div', {'class': 'code-output'})

        # If not HTML, add the `pre` class so that we know to render output as raw text
        if not block_is_html and 'pre' not in output.get('class', 'code-output'):
            output.set('class', ' '.join([output.get('class', ''), 'pre']))

        output.text = "{}\n".format(block) if block_is_html else AtomicString("{}\n".format(block))

        if theRest:
            # This block contained unindented line(s) after the first indented
            # line. Insert these lines as the first block of the master blocks
            # list for future processing.
            blocks.insert(0, theRest)

def handleMatch(self, m):
        node = markdown.util.etree.Element('mathjax')
        node.text = markdown.util.AtomicString(m.group(2) + m.group(3) + m.group(2))
        return node

def handleMatch(self, m):
        node = markdown.util.etree.Element('mathjax')
        node.text = markdown.util.AtomicString(m.group(2) + m.group(3) + m.group(2))
        return node