1 files changed, 87 insertions, 0 deletions
diff --git a/doc/sphinxext/only_directives.py b/doc/sphinxext/only_directives.py
new file mode 100644
index 000000000..e4dfd5cc7
--- /dev/null
+++ b/doc/sphinxext/only_directives.py
@@ -0,0 +1,87 @@
+#
+# A pair of directives for inserting content that will only appear in
+# either html or latex.
+#
+
+from docutils.nodes import Body, Element
+from docutils.writers.html4css1 import HTMLTranslator
+from sphinx.latexwriter import LaTeXTranslator
+from docutils.parsers.rst import directives
+
+class html_only(Body, Element):
+    pass
+
+class latex_only(Body, Element):
+    pass
+
+def run(content, node_class, state, content_offset):
+    text = '\n'.join(content)
+    node = node_class(text)
+    state.nested_parse(content, content_offset, node)
+    return [node]
+
+try:
+    from docutils.parsers.rst import Directive
+except ImportError:
+    from docutils.parsers.rst.directives import _directives
+
+    def html_only_directive(name, arguments, options, content, lineno,
+                            content_offset, block_text, state, state_machine):
+        return run(content, html_only, state, content_offset)
+
+    def latex_only_directive(name, arguments, options, content, lineno,
+                             content_offset, block_text, state, state_machine):
+        return run(content, latex_only, state, content_offset)
+
+    for func in (html_only_directive, latex_only_directive):
+        func.content = 1
+        func.options = {}
+        func.arguments = None
+
+    _directives['htmlonly'] = html_only_directive
+    _directives['latexonly'] = latex_only_directive
+else:
+    class OnlyDirective(Directive):
+        has_content = True
+        required_arguments = 0
+        optional_arguments = 0
+        final_argument_whitespace = True
+        option_spec = {}
+
+        def run(self):
+            self.assert_has_content()
+            return run(self.content, self.node_class,
+                       self.state, self.content_offset)
+
+    class HtmlOnlyDirective(OnlyDirective):
+        node_class = html_only
+
+    class LatexOnlyDirective(OnlyDirective):
+        node_class = latex_only
+
+    directives.register_directive('htmlonly', HtmlOnlyDirective)
+    directives.register_directive('latexonly', LatexOnlyDirective)
+
+def setup(app):
+    app.add_node(html_only)
+    app.add_node(latex_only)
+
+    # Add visit/depart methods to HTML-Translator:
+    def visit_perform(self, node):
+        pass
+    def depart_perform(self, node):
+        pass
+    def visit_ignore(self, node):
+        node.children = []
+    def depart_ignore(self, node):
+        node.children = []
+
+    HTMLTranslator.visit_html_only = visit_perform
+    HTMLTranslator.depart_html_only = depart_perform
+    HTMLTranslator.visit_latex_only = visit_ignore
+    HTMLTranslator.depart_latex_only = depart_ignore
+
+    LaTeXTranslator.visit_html_only = visit_ignore
+    LaTeXTranslator.depart_html_only = depart_ignore
+    LaTeXTranslator.visit_latex_only = visit_perform
+    LaTeXTranslator.depart_latex_only = depart_perform