1 files changed, 57 insertions, 0 deletions
diff --git a/src/mistune/plugins/math.py b/src/mistune/plugins/math.py
new file mode 100644
index 0000000..805105e
--- /dev/null
+++ b/src/mistune/plugins/math.py
@@ -0,0 +1,57 @@
+__all__ = ['math', 'math_in_quote', 'math_in_list']
+
+BLOCK_MATH_PATTERN = r'^ {0,3}\$\$[ \t]*\n(?P<math_text>[\s\S]+?)\n\$\$[ \t]*$'
+INLINE_MATH_PATTERN = r'\$(?!\s)(?P<math_text>.+?)(?!\s)\$'
+
+
+def parse_block_math(block, m, state):
+    text = m.group('math_text')
+    state.append_token({'type': 'block_math', 'raw': text})
+    return m.end() + 1
+
+
+def parse_inline_math(inline, m, state):
+    text = m.group('math_text')
+    state.append_token({'type': 'inline_math', 'raw': text})
+    return m.end()
+
+
+def render_block_math(renderer, text):
+    return '<div class="math">$$\n' + text + '\n$$</div>\n'
+
+
+def render_inline_math(renderer, text):
+    return r'<span class="math">\(' + text + r'\)</span>'
+
+
+def math(md):
+    """A mistune plugin to support math. The syntax is used
+    by many markdown extensions:
+
+    .. code-block:: text
+
+        Block math is surrounded by $$:
+
+        $$
+        f(a)=f(b)
+        $$
+
+        Inline math is surrounded by `$`, such as $f(a)=f(b)$
+
+    :param md: Markdown instance
+    """
+    md.block.register('block_math', BLOCK_MATH_PATTERN, parse_block_math, before='list')
+    md.inline.register('inline_math', INLINE_MATH_PATTERN, parse_inline_math, before='link')
+    if md.renderer and md.renderer.NAME == 'html':
+        md.renderer.register('block_math', render_block_math)
+        md.renderer.register('inline_math', render_inline_math)
+
+
+def math_in_quote(md):
+    """Enable block math plugin in block quote."""
+    md.block.insert_rule(md.block.block_quote_rules, 'block_math', before='list')
+
+
+def math_in_list(md):
+    """Enable block math plugin in list."""
+    md.block.insert_rule(md.block.list_rules, 'block_math', before='list')