It is "if(not <variable>)"

[[Imported from SVN: r6687]]

cmake/modules/DuneDoc.cmake

@@ -2,23 +2,24 @@ FIND_PACKAGE(LATEX)
 FIND_PROGRAM(IMAGEMAGICK_CONVERT convert
   DOC "The convert program that comes with ImageMagick (available at http://www.imagemagick.org)."
   )
-set(LATEX_USABLE ON)
-if(NOT ${LATEX_COMPILER})
+set(LATEX_USABLE "ON")
+
+if(NOT LATEX_COMPILER)
   message(WARING " Need latex to create documentation!")
   set(LATEX_USABLE)
-endif(NOT ${LATEX_COMPILER})
-if(NOT ${BIBTEX_COMPILER})
+endif(NOT LATEX_COMPILER)
+if(NOT BIBTEX_COMPILER)
   message(WARING " Need bibtex to create documentation!")
   set(LATEX_USABLE)
-endif(NOT ${BIBTEX_COMPILER})
-if(NOT ${MAKEINDEX_COMPILER})
+endif(NOT BIBTEX_COMPILER)
+if(NOT MAKEINDEX_COMPILER)
   message(WARING " Need makeindex to create documentation!")
   set(LATEX_USABLE)
-endif(NOT ${MAKEINDEX_COMPILER})
-if(NOT ${IMAGEMAGICK_CONVERT})
+endif(NOT MAKEINDEX_COMPILER)
+if(NOT IMAGEMAGICK_CONVERT)
   message(WARNING " Need imagemagick to create latex documentation!")
   set(LATEX_USABLE)
-endif(NOT ${IMAGEMAGICK_CONVERT})
+endif(NOT IMAGEMAGICK_CONVERT)
 if(LATEX_USABLE)
   include(UseLATEX)
 endif(LATEX_USABLE)