ENH: parse version for muParserX

CMake/FindMuParserX.cmake

 # Find MuParserX
 #
-#   MUPARSERX_FOUND        - True if MuParser found.
+#   MUPARSERX_FOUND        - True if MuParserX found.
 #   MUPARSERX_INCLUDE_DIRS - where to find mpParser.h, etc.
-#   MUPARSERX_LIBRARIES    - List of libraries when using MuParser.
+#   MUPARSERX_LIBRARIES    - List of libraries when using MuParserX.
+#   MUPARSERX_VERSION        - version string
+#   MUPARSERX_VERSION_MAJOR  - version major number
+#   MUPARSERX_VERSION_MINOR  - version minor number
+#   MUPARSERX_VERSION_PATCH  - version patch number
+#   MUPARSERX_VERSION_NUMBER - version number ((major*100)+minor)*100+patch
 #
 
 if( MUPARSERX_INCLUDE_DIR )
@@ -13,6 +18,21 @@ endif()
 find_path( MUPARSERX_INCLUDE_DIR mpParser.h
            PATH_SUFFIXES mpParser )
 
+if(EXISTS "${MUPARSERX_INCLUDE_DIR}/mpDefines.h")
+  file(READ "${MUPARSERX_INCLUDE_DIR}/mpDefines.h" _mpDefines_h_CONTENTS)
+  string(REGEX REPLACE ".*# *define MUP_PARSER_VERSION *_T\\(\"([0-9.]+)( .*)?\"\\).*" "\\1" MUPARSERX_VERSION "${_mpDefines_h_CONTENTS}")
+  string(REGEX REPLACE "([0-9]+)\\.([0-9]+)\\.([0-9]+)" "\\1" MUPARSERX_VERSION_MAJOR "${MUPARSERX_VERSION}")
+  string(REGEX REPLACE "([0-9]+)\\.([0-9]+)\\.([0-9]+)" "\\2" MUPARSERX_VERSION_MINOR "${MUPARSERX_VERSION}")
+  string(REGEX REPLACE "([0-9]+)\\.([0-9]+)\\.([0-9]+)" "\\3" MUPARSERX_VERSION_PATCH "${MUPARSERX_VERSION}")
+  math(EXPR MUPARSERX_VERSION_NUMBER
+    "((${MUPARSERX_VERSION_MAJOR})*100+${MUPARSERX_VERSION_MINOR})*100+${MUPARSERX_VERSION_PATCH}")
+else()
+  if(NOT MuParserX_FIND_QUIETLY)
+  message(WARNING "mpDefines.h not found !")
+  endif()
+endif()
+
+
 find_library( MUPARSERX_LIBRARY
               NAMES muparserx
               PATH_SUFFIXES muparserx )