cmake_parse_argumentsΒΆ
Parse function or macro arguments.
cmake_parse_arguments(<prefix> <options> <one_value_keywords>
<multi_value_keywords> <args>...)
cmake_parse_arguments(PARSE_ARGV <N> <prefix> <options>
<one_value_keywords> <multi_value_keywords>)
New in version 3.5: This command is implemented natively. Previously, it has been defined in the
module CMakeParseArguments
.
This command is for use in macros or functions. It processes the arguments given to that macro or function, and defines a set of variables which hold the values of the respective options.
The first signature reads processes arguments passed in the <args>...
.
This may be used in either a macro()
or a function()
.
New in version 3.7: The PARSE_ARGV
signature is only for use in a function()
body. In this case the arguments that are parsed come from the
ARGV#
variables of the calling function. The parsing starts with
the <N>
-th argument, where <N>
is an unsigned integer.
This allows for the values to have special characters like ;
in them.
The <options>
argument contains all options for the respective macro,
i.e. keywords which can be used when calling the macro without any value
following, like e.g. the OPTIONAL
keyword of the install()
command.
The <one_value_keywords>
argument contains all keywords for this macro
which are followed by one value, like e.g. DESTINATION
keyword of the
install()
command.
The <multi_value_keywords>
argument contains all keywords for this
macro which can be followed by more than one value, like e.g. the
TARGETS
or FILES
keywords of the install()
command.
Changed in version 3.5: All keywords shall be unique. I.e. every keyword shall only be specified
once in either <options>
, <one_value_keywords>
or
<multi_value_keywords>
. A warning will be emitted if uniqueness is
violated.
When done, cmake_parse_arguments
will consider for each of the
keywords listed in <options>
, <one_value_keywords>
and
<multi_value_keywords>
a variable composed of the given <prefix>
followed by "_"
and the name of the respective keyword. These
variables will then hold the respective value from the argument list
or be undefined if the associated option could not be found.
For the <options>
keywords, these will always be defined,
to TRUE
or FALSE
, whether the option is in the argument list or not.
All remaining arguments are collected in a variable
<prefix>_UNPARSED_ARGUMENTS
that will be undefined if all arguments
were recognized. This can be checked afterwards to see
whether your macro was called with unrecognized parameters.
New in version 3.15: <one_value_keywords>
and <multi_value_keywords>
that were given no
values at all are collected in a variable
<prefix>_KEYWORDS_MISSING_VALUES
that will be undefined if all keywords
received values. This can be checked to see if there were keywords without
any values given.
Consider the following example macro, my_install()
, which takes similar
arguments to the real install()
command:
macro(my_install)
set(options OPTIONAL FAST)
set(oneValueArgs DESTINATION RENAME)
set(multiValueArgs TARGETS CONFIGURATIONS)
cmake_parse_arguments(MY_INSTALL "${options}" "${oneValueArgs}"
"${multiValueArgs}" ${ARGN} )
# ...
Assume my_install()
has been called like this:
my_install(TARGETS foo bar DESTINATION bin OPTIONAL blub CONFIGURATIONS)
After the cmake_parse_arguments
call the macro will have set or undefined
the following variables:
MY_INSTALL_OPTIONAL = TRUE
MY_INSTALL_FAST = FALSE # was not used in call to my_install
MY_INSTALL_DESTINATION = "bin"
MY_INSTALL_RENAME <UNDEFINED> # was not used
MY_INSTALL_TARGETS = "foo;bar"
MY_INSTALL_CONFIGURATIONS <UNDEFINED> # was not used
MY_INSTALL_UNPARSED_ARGUMENTS = "blub" # nothing expected after "OPTIONAL"
MY_INSTALL_KEYWORDS_MISSING_VALUES = "CONFIGURATIONS"
# No value for "CONFIGURATIONS" given
You can then continue and process these variables.
Keywords terminate lists of values, e.g. if directly after a
one_value_keyword
another recognized keyword follows, this is
interpreted as the beginning of the new option. E.g.
my_install(TARGETS foo DESTINATION OPTIONAL)
would result in
MY_INSTALL_DESTINATION
set to "OPTIONAL"
, but as OPTIONAL
is a keyword itself MY_INSTALL_DESTINATION
will be empty (but added
to MY_INSTALL_KEYWORDS_MISSING_VALUES
) and MY_INSTALL_OPTIONAL
will
therefore be set to TRUE
.