Help: Workaround pygments reporting an error for genexes.

Without the workaround, CMake code snippets are not highlighted
at all because pygments can not lex the generator expressions.

Utilities/Sphinx/cmake.py

@@ -12,6 +12,16 @@
 import os
 import re
 
+# Monkey patch for pygments reporting an error when generator expressions are
+# used.
+# https://bitbucket.org/birkenfeld/pygments-main/issue/942/cmake-generator-expressions-not-handled
+from pygments.lexers import CMakeLexer
+from pygments.token import Name, Operator
+from pygments.lexer import bygroups
+CMakeLexer.tokens["args"].append(('(\\$<)(.+?)(>)',
+                                  bygroups(Operator, Name.Variable, Operator)))
+
+
 from docutils.parsers.rst import Directive, directives
 from docutils.transforms import Transform
 try: