_lxml.py 文件源码

def start(self, name, attrs, nsmap={}):
        # Make sure attrs is a mutable dict--lxml may send an immutable dictproxy.
        attrs = dict(attrs)

        nsprefix = None
        # Invert each namespace map as it comes in.
        if len(nsmap) == 0 and self.nsmaps != None:
            # There are no new namespaces for this tag, but namespaces
            # are in play, so we need a separate tag stack to know
            # when they end.
            self.nsmaps.append(None)
        elif len(nsmap) > 0:
            # A new namespace mapping has come into play.
            if self.nsmaps is None:
                self.nsmaps = []
            inverted_nsmap = dict((value, key) for key, value in nsmap.items())
            self.nsmaps.append(inverted_nsmap)
            # Also treat the namespace mapping as a set of attributes on the
            # tag, so we can recreate it later.
            attrs = attrs.copy()
            for prefix, namespace in nsmap.items():
                attribute = NamespacedAttribute(
                    "xmlns", prefix, "http://www.w3.org/2000/xmlns/")
                attrs[attribute] = namespace
        namespace, name = self._getNsTag(name)
        if namespace is not None:
            for inverted_nsmap in reversed(self.nsmaps):
                if inverted_nsmap is not None and namespace in inverted_nsmap:
                    nsprefix = inverted_nsmap[namespace]
                    break
        self.soup.handle_starttag(name, namespace, nsprefix, attrs)