universal.py 文件源码

def apply(self):
        smart_quotes = self.document.settings.smart_quotes
        if not smart_quotes:
            return
        try:
            alternative = smart_quotes.startswith('alt')
        except AttributeError:
            alternative = False
        # print repr(alternative)

        document_language = self.document.settings.language_code

        # "Educate" quotes in normal text. Handle each block of text
        # (TextElement node) as a unit to keep context around inline nodes:
        for node in self.document.traverse(nodes.TextElement):
            # skip preformatted text blocks and special elements:
            if isinstance(node, (nodes.FixedTextElement, nodes.Special)):
                continue
            # nested TextElements are not "block-level" elements:
            if isinstance(node.parent, nodes.TextElement):
                continue

            # list of text nodes in the "text block":
            txtnodes = [txtnode for txtnode in node.traverse(nodes.Text)
                        if not isinstance(txtnode.parent,
                                          nodes.option_string)]

            # language: use typographical quotes for language "lang"
            lang = node.get_language_code(document_language)
            # use alternative form if `smart-quotes` setting starts with "alt":
            if alternative:
                if '-x-altquot' in lang:
                    lang = lang.replace('-x-altquot', '')
                else:
                    lang += '-x-altquot'
            # drop subtags missing in quotes:
            for tag in utils.normalize_language_tag(lang):
                if tag in smartquotes.smartchars.quotes:
                    lang = tag
                    break
            else: # language not supported: (keep ASCII quotes)
                if lang not in self.unsupported_languages:
                    self.document.reporter.warning('No smart quotes '
                        'defined for language "%s".'%lang, base_node=node)
                self.unsupported_languages.add(lang)
                lang = ''

            # Iterator educating quotes in plain text:
            # '2': set all, using old school en- and em- dash shortcuts
            teacher = smartquotes.educate_tokens(self.get_tokens(txtnodes),
                                                 attr='2', language=lang)

            for txtnode, newtext in zip(txtnodes, teacher):
                txtnode.parent.replace(txtnode, nodes.Text(newtext))

            self.unsupported_languages = set() # reset