list¶
List operations.
list(LENGTH <list> <output variable>)
list(GET <list> <element index> [<element index> ...]
<output variable>)
list(APPEND <list> [<element> ...])
list(FILTER <list> <INCLUDE|EXCLUDE> REGEX <regular_expression>)
list(FIND <list> <value> <output variable>)
list(INSERT <list> <element_index> <element> [<element> ...])
list(REMOVE_ITEM <list> <value> [<value> ...])
list(REMOVE_AT <list> <index> [<index> ...])
list(REMOVE_DUPLICATES <list>)
list(REVERSE <list>)
list(SORT <list>)
LENGTH
will return a given list’s length.
GET
will return list of elements specified by indices from the list.
APPEND
will append elements to the list.
FILTER
will include or remove items from the list that match the
mode’s pattern.
In REGEX
mode, items will be matched against the given regular expression.
For more information on regular expressions see also the string()
command.
FIND
will return the index of the element specified in the list or -1
if it wasn’t found.
INSERT
will insert elements to the list to the specified location.
REMOVE_AT
and REMOVE_ITEM
will remove items from the list. The
difference is that REMOVE_ITEM
will remove the given items, while
REMOVE_AT
will remove the items at the given indices.
REMOVE_DUPLICATES
will remove duplicated items in the list.
REVERSE
reverses the contents of the list in-place.
SORT
sorts the list in-place alphabetically.
The list subcommands APPEND
, INSERT
, FILTER
, REMOVE_AT
,
REMOVE_ITEM
, REMOVE_DUPLICATES
, REVERSE
and SORT
may create new
values for the list within the current CMake variable scope. Similar to the
set()
command, the LIST command creates new variable values in the
current scope, even if the list itself is actually defined in a parent
scope. To propagate the results of these operations upwards, use
set()
with PARENT_SCOPE
, set()
with
CACHE INTERNAL
, or some other means of value propagation.
NOTES: A list in cmake is a ;
separated group of strings. To create a
list the set command can be used. For example, set(var a b c d e)
creates a list with a;b;c;d;e
, and set(var "a b c d e")
creates a
string or a list with one item in it. (Note macro arguments are not
variables, and therefore cannot be used in LIST commands.)
When specifying index values, if <element index>
is 0 or greater, it
is indexed from the beginning of the list, with 0 representing the
first list element. If <element index>
is -1 or lesser, it is indexed
from the end of the list, with -1 representing the last list element.
Be careful when counting with negative indices: they do not start from
0. -0 is equivalent to 0, the first list element.