#
#  $Id: parse_arguments.cmake 169709 2012-11-04 16:17:04Z nwhitehorn $
#

# The PARSE_ARGUMENTS macro will take the arguments of another macro and
# define several variables. The first argument to PARSE_ARGUMENTS is a
# prefix to put on all variables it creates. The second argument is a
# list of names, and the third argument is a list of options. Both of
# these lists should be quoted. The rest of PARSE_ARGUMENTS are
# arguments from another macro to be parsed.
# 
#     PARSE_ARGUMENTS(prefix arg_names options arg1 arg2...) 
# 
# For each item in options, PARSE_ARGUMENTS will create a variable with
# that name, prefixed with prefix_. So, for example, if prefix is
# MY_MACRO and options is OPTION1;OPTION2, then PARSE_ARGUMENTS will
# create the variables MY_MACRO_OPTION1 and MY_MACRO_OPTION2. These
# variables will be set to true if the option exists in the command line
# or false otherwise.
# 
# For each item in arg_names, PARSE_ARGUMENTS will create a variable
# with that name, prefixed with prefix_. Each variable will be filled
# with the arguments that occur after the given arg_name is encountered
# up to the next arg_name or the end of the arguments. All options are
# removed from these lists. PARSE_ARGUMENTS also creates a
# prefix_DEFAULT_ARGS variable containing the list of all arguments up
# to the first arg_name encountered.
MACRO(PARSE_ARGUMENTS prefix arg_names option_names)
  SET(DEFAULT_ARGS)
  FOREACH(arg_name ${arg_names})
    SET(${prefix}_${arg_name})
  ENDFOREACH(arg_name)
  FOREACH(option ${option_names})
    SET(${prefix}_${option} FALSE)
  ENDFOREACH(option)

  SET(current_arg_name DEFAULT_ARGS)
  SET(current_arg_list)
  FOREACH(arg ${ARGN})
    LIST_CONTAINS(is_arg_name ${arg} ${arg_names})
    IF (is_arg_name)
      SET(${prefix}_${current_arg_name} ${current_arg_list})
      SET(current_arg_name ${arg})
      SET(current_arg_list)
    ELSE (is_arg_name)
      LIST_CONTAINS(is_option ${arg} ${option_names})
      IF (is_option)
      SET(${prefix}_${arg} TRUE)
      ELSE (is_option)
      SET(current_arg_list ${current_arg_list} ${arg})
      ENDIF (is_option)
    ENDIF (is_arg_name)
  ENDFOREACH(arg)
  SET(${prefix}_${current_arg_name} ${current_arg_list})
ENDMACRO(PARSE_ARGUMENTS)

