#Dump Variables

#dump()

Outputs the names and values of given variables. Behind the scene, var_dump() is used.

set(build_assets true)
set(assets_dir "/home/code/my-project/resources")

dump(
    build_assets
    assets_dir
)

message("Onward...")

The above will output a WARNING message, and continue to process your cmake script:

CMake Warning at cmake/rsp/debug.cmake:31 (message):
dump:

   build_assets = (bool) true
   assets_dir = (string 31) "/home/code/my-project/resources"
Call Stack (most recent call first):
  CMakeLists.txt:132 (dump)

Onward...

#dd()

Outputs the names and values of given variables, and stops the build (dump and die). Behind the scene, var_dump() is used.

set(build_assets true)
set(assets_dir "/home/code/my-project/resources")

dd(
    build_assets
    assets_dir
)

# This message will never be reached!
message("Onward...")

The dd() function will output using cmake’s FATAL_ERROR message mode. Your cmake script will not continue to be processed:

CMake Error at cmake/rsp/debug.cmake:54 (message):
dd:

   build_assets = (bool) true
   assets_dir = (string 31) "/home/code/my-project/resources"
Call Stack (most recent call first):
  CMakeLists.txt:132 (dd)

#var_dump()

Outputs human-readable information about given properties. It accepts the following parameters:

• PROPERTIES: The variables to be dumped.
• OUTPUT: (optional), output variable. If specified, message is assigned to variable, instead of being printed to stdout or stderr.
• WITHOUT_NAMES: (option), Output information without the variable names.
• IGNORE_LIST: (option), Variables of the type “list” are treated as “string” type instead.

set(my_str "Hi there")
set(my_empty_str "")
set(my_num 23)
set(my_float 1.1234)
set(my_bool true)
set(my_const on)
set(my_list "foo;bar;42;true")
set(my_cached_prop "My cached var..." CACHE STRING "Testing")
set(ENV{my_env_prop} "/home/other/place")

macro(my_macro)
endmacro()

function(my_function)
endfunction()

var_dump(PROPERTIES
    my_str
    my_empty_str
    my_num
    my_float
    my_const
    my_undefined_prop
    my_list
    my_cached_prop
    my_env_prop
    my_macro
    my_function
)

The above will output:

my_str = (string 8) "Hi there"
my_empty_str = (string 0) ""
my_num = (int) 23
my_float = (float) 1.1234
my_const = (string 2) "on"
my_undefined_prop = (undefined) 
my_list = (list 4) [ 
   0: (string 3) "foo"
   1: (string 3) "bar"
   2: (int) 42
   3: (bool) true
]
my_cached_prop = (string 4, cached) "Yolo"
my_env_prop = (string 17, ENV) "/home/other/place"
my_macro = (command) my_macro()
my_function = (command) my_function()

#Without Names

If the WITHOUT_NAMES option is set, then variable names are not part of the output.

var_dump(
    WITHOUT_NAMES
    PROPERTIES
        my_str
)

Outputs:

(string 8) "Hi there"

#Ignore List

By default, var_dump() will attempt to parse any list variable and output each item on a new line. To disable this behaviour, set the IGNORE_LIST option. When doing so, lists are treated as a regular string.

Default behaviour

var_dump(
    PROPERTIES
        my_list
)

Outputs:

my_list = (list 4) [ 
   0: (string 3) "foo"
   1: (string 3) "bar"
   2: (int) 42
   3: (bool) true
]

With ignore list option

var_dump(
    IGNORE_LIST
    PROPERTIES
        my_list
)

Outputs:

my_list = (string 15) "foo;bar;42;true"