Fixes the way conditions are checked on variables so it is correct. (#780)

examples/quickstart/CMakeLists.txt

@@ -14,14 +14,14 @@ IF(${CMAKE_SYSTEM_NAME} MATCHES "Linux")
   function(add_quickstart_test TEST_NAME SOURCE_FILE)
     # Second argument is C++ standard name
     if (MSVC)
-      if (${ARGV2})
+      if (ARGV2)
         set(QUICKSTART_FLAGS /std:${ARGV2})
       else()
         set(QUICKSTART_FLAGS /WX)
       endif()
       set(QUICKSTART_INCLUDE /I${PROJECT_SOURCE_DIR}/include /I${PROJECT_SOURCE_DIR}/src ${PROJECT_SOURCE_DIR}/src/simdjson.cpp)
     else()
-      if (${ARGV2})
+      if (ARGV2)
         set(QUICKSTART_FLAGS -Werror -std=${ARGV2})
       else()
         set(QUICKSTART_FLAGS -Werror)
@@ -30,7 +30,7 @@ IF(${CMAKE_SYSTEM_NAME} MATCHES "Linux")
     endif()
 
     # Third argument tells whether to compile with -fno-exceptions
-    if (${ARGV3})
+    if (ARGV3)
       if (NOT MSVC)
         set(QUICKSTART_FLAGS ${QUICKSTART_FLAGS} -fno-exceptions)
       endif()