#
#Flex lexical analyzer
#

if (WIN32)
#Building flex from source using Visual Studio is a hopeless case.
#Install from a binary distribution instead.
ExternalProject_Add (
  flex
  PREFIX ${CMAKE_INSTALL_PREFIX}
  BUILD_IN_SOURCE 1
  URL http://sourceforge.net/projects/winflexbison/files/win_flex_bison-2.5.9.zip
  URL_MD5 c32b74a34d91cbdbaecff8390669ae72
  UPDATE_COMMAND ""
  CONFIGURE_COMMAND ""
  BUILD_COMMAND ""
  INSTALL_COMMAND ${CMAKE_COMMAND} -DCMAKE_INSTALL_PREFIX=<INSTALL_DIR> -P ${CMAKE_CURRENT_LIST_DIR}/install.cmake
)
endif (WIN32)

if (UNIX)
#Rely on manual installation via the package manager
#You can then invoke flex as /usr/bin/flex
#sudo apt-get -q -y install flex
ExternalProject_Add (
  flex
  PREFIX ${CMAKE_INSTALL_PREFIX}
  BUILD_IN_SOURCE 1
  DOWNLOAD_COMMAND ""
  UPDATE_COMMAND ""
  CONFIGURE_COMMAND ""
  BUILD_COMMAND /usr/bin/flex --version
  INSTALL_COMMAND ""
)
endif (UNIX)