1# Copied from http://www.itk.org/Wiki/CMakeMacroParseArguments under
2# http://creativecommons.org/licenses/by/2.5/.
3#
4# The PARSE_ARGUMENTS macro will take the arguments of another macro and define
5# several variables. The first argument to PARSE_ARGUMENTS is a prefix to put on
6# all variables it creates. The second argument is a list of names, and the
7# third argument is a list of options. Both of these lists should be quoted. The
8# rest of PARSE_ARGUMENTS are arguments from another macro to be parsed.
9#
10# PARSE_ARGUMENTS(prefix arg_names options arg1 arg2...)
11#
12# For each item in options, PARSE_ARGUMENTS will create a variable with that
13# name, prefixed with prefix_. So, for example, if prefix is MY_MACRO and
14# options is OPTION1;OPTION2, then PARSE_ARGUMENTS will create the variables
15# MY_MACRO_OPTION1 and MY_MACRO_OPTION2. These variables will be set to true if
16# the option exists in the command line or false otherwise.
17#
18#For each item in arg_names, PARSE_ARGUMENTS will create a variable with that
19#name, prefixed with prefix_. Each variable will be filled with the arguments
20#that occur after the given arg_name is encountered up to the next arg_name or
21#the end of the arguments. All options are removed from these
22#lists. PARSE_ARGUMENTS also creates a prefix_DEFAULT_ARGS variable containing
23#the list of all arguments up to the first arg_name encountered.
24#
25#Here is a simple, albeit impractical, example of using PARSE_ARGUMENTS that
26#demonstrates its behavior.
27#
28# SET(arguments
29#     hello OPTION3 world
30#     LIST3 foo bar
31#     OPTION2
32#     LIST1 fuz baz
33#     )
34#
35# PARSE_ARGUMENTS(ARG "LIST1;LIST2;LIST3" "OPTION1;OPTION2;OPTION3" ${arguments})
36#
37# PARSE_ARGUMENTS creates 7 variables and sets them as follows:
38#   ARG_DEFAULT_ARGS: hello;world
39#   ARG_LIST1: fuz;baz
40#   ARG_LIST2:
41#   ARG_LIST3: foo;bar
42#   ARG_OPTION1: FALSE
43#   ARG_OPTION2: TRUE
44#   ARG_OPTION3: TRUE
45#
46# If you don't have any options, use an empty string in its place.
47#   PARSE_ARGUMENTS(ARG "LIST1;LIST2;LIST3" "" ${arguments})
48# Likewise if you have no lists.
49#   PARSE_ARGUMENTS(ARG "" "OPTION1;OPTION2;OPTION3" ${arguments})
50
51MACRO(PARSE_ARGUMENTS prefix arg_names option_names)
52  SET(DEFAULT_ARGS)
53  FOREACH(arg_name ${arg_names})
54    SET(${prefix}_${arg_name})
55  ENDFOREACH(arg_name)
56  FOREACH(option ${option_names})
57    SET(${prefix}_${option} FALSE)
58  ENDFOREACH(option)
59
60  SET(current_arg_name DEFAULT_ARGS)
61  SET(current_arg_list)
62  FOREACH(arg ${ARGN})
63    SET(larg_names ${arg_names})
64    LIST(FIND larg_names "${arg}" is_arg_name)
65    IF (is_arg_name GREATER -1)
66      SET(${prefix}_${current_arg_name} ${current_arg_list})
67      SET(current_arg_name ${arg})
68      SET(current_arg_list)
69    ELSE (is_arg_name GREATER -1)
70      SET(loption_names ${option_names})
71      LIST(FIND loption_names "${arg}" is_option)
72      IF (is_option GREATER -1)
73        SET(${prefix}_${arg} TRUE)
74      ELSE (is_option GREATER -1)
75        SET(current_arg_list ${current_arg_list} ${arg})
76      ENDIF (is_option GREATER -1)
77    ENDIF (is_arg_name GREATER -1)
78  ENDFOREACH(arg)
79  SET(${prefix}_${current_arg_name} ${current_arg_list})
80ENDMACRO(PARSE_ARGUMENTS)
81