# Including a .cmake file

**URL:** https://discourse.cmake.org/t/including-a-cmake-file/7034
**Category:** Usage
**Created:** [December 8, 2022, 10:25am UTC](https://discourse.cmake.org/t/including-a-cmake-file/7034 "2022-12-08T10:25:18Z")
**Posts on this page:** 6
**Page:** 1

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### Author: ![willem](https://discourse.cmake.org/letter_avatar_proxy/v4/letter/w/898d66/32.png) [@willem](https://discourse.cmake.org/u/willem)
#### Post date: [December 8, 2022, 10:25am UTC](https://discourse.cmake.org/t/including-a-cmake-file/7034/1 "2022-12-08T10:25:18Z")

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I have top-level cmakelists, with in subdirectory “cmake” a file “dependencies.cmake”. I cannot seem to include it following the approach in professional cmake book. See below? Can anybody explain what is going on? What is a portable approach for including a

Top-level cmakelists:

```cmake
cmake_minimum_required (VERSION 3.21)
project ("projname" CXX)

# PROJECT WIDE SETUP

list(APPEND CMAKE_MODULE_PATH ${CMAKE_CURRENT_LIST_DIR}/cmake)
set(CMAKE_CXX_STANDARD 20)
set(CMAKE_CXX_STANDARD_REQUIRED YES)
set(CMAKE_CXX_EXTENSIONS NO)

#shows the correct path, so appending worked.
message(module ${CMAKE_MODULE_PATH})

# DEPENDENCIES
#does not work, even though this is listed in professional cmake book:
include(dependencies.cmake)
#does seem to work for MSVC, but is this portable?! 
#include(dependencies)

# etc. 

```

Output:

```auto
1> [CMake] -- The CXX compiler identification is MSVC 19.32.31329.0
1> [CMake] -- Detecting CXX compiler ABI info
1> [CMake] -- Detecting CXX compiler ABI info - done
1> [CMake] -- Check for working CXX compiler: C:/Program Files/Microsoft Visual Studio/2022/Community/VC/Tools/MSVC/14.32.31326/bin/Hostx64/x64/cl.exe - skipped
1> [CMake] -- Detecting CXX compile features
1> [CMake] -- Detecting CXX compile features - done
1> [CMake] moduleC:/Users/<user>/source/repos/LibraryTests/cmake
1> [CMake] CMake Error at C:\Users\<user>\source\repos\LibraryTests\CMakeLists.txt:16 (include):
1> [CMake] include could not find requested file:
1> [CMake] 
1> [CMake] dependencies.cmake

```

Interestingly, when I put the dependencies.cmake in the outmost directory (alongside cmakelists.txt ) both cases work.

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### Author: ![ben.boeckel](https://discourse.cmake.org/letter_avatar_proxy/v4/letter/b/ea5d25/32.png) [@ben.boeckel](https://discourse.cmake.org/u/ben.boeckel)
#### Post date: [December 8, 2022, 1:35pm UTC](https://discourse.cmake.org/t/including-a-cmake-file/7034/2 "2022-12-08T13:35:45Z")

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From [the docs for `include`](https://cmake.org/cmake/help/latest/command/include.html):

> If a module is specified instead of a file, the file with name `<modulename>.cmake` is searched first in [`CMAKE_MODULE_PATH`](https://cmake.org/cmake/help/latest/variable/CMAKE_MODULE_PATH.html#variable:CMAKE_MODULE_PATH), then in the CMake module directory.

So CMake first searches for a file named `dependencies.cmake` relative to the `CMAKE_CURRENT_LIST_DIR` (I think; it might be `CMAKE_CURRENT_SOURCE_DIR`?). If it doesn’t find it, it searches for it in `CMAKE_MODULE_PATH` with a `.cmake` extension. So you can either use an absolute path or the name of the file (without `.cmake`) and use `CMAKE_MODULE_PATH`.

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### Author: ![willem](https://discourse.cmake.org/letter_avatar_proxy/v4/letter/w/898d66/32.png) [@willem](https://discourse.cmake.org/u/willem)
#### Post date: [December 8, 2022, 2:59pm UTC](https://discourse.cmake.org/t/including-a-cmake-file/7034/3 "2022-12-08T14:59:12Z")

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Ah, that clarifies, so calling include for the filename without appendix is the correct thing.

Strange typo in the book.

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### Author: ![ben.boeckel](https://discourse.cmake.org/letter_avatar_proxy/v4/letter/b/ea5d25/32.png) [@ben.boeckel](https://discourse.cmake.org/u/ben.boeckel)
#### Post date: [December 8, 2022, 4:05pm UTC](https://discourse.cmake.org/t/including-a-cmake-file/7034/4 "2022-12-08T16:05:46Z")

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@craig.scott FYI

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### Author: ![craig.scott](https://discourse.cmake.org/user_avatar/discourse.cmake.org/craig.scott/32/20_2.png) [@craig.scott](https://discourse.cmake.org/u/craig.scott)
#### Post date: [December 8, 2022, 9:22pm UTC](https://discourse.cmake.org/t/including-a-cmake-file/7034/5 "2022-12-08T21:22:56Z")

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The last edition had some updates in that part of the book, but it could use further revising of some wording around the change from using `add_subdirectory()` to `include()` to bring in dependencies. My recommendation now is to put your `dependencies.cmake` in the top-most directory, not in a subdirectory. This is stated later in the text, but the earlier parts still read as though putting it in a subdirectory is recommended. I’ll address this in the next edition.

For your specific query, using `include(dependencies.cmake)` is correct, but the `dependencies.cmake` file should be in the same directory. I would not recommend using `include(dependencies)` and relying on `CMAKE_MODULE_PATH` because in this case, you want to load a very specific file at a specific location. You shouldn’t need to search for it.

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### Author: ![willem](https://discourse.cmake.org/letter_avatar_proxy/v4/letter/w/898d66/32.png) [@willem](https://discourse.cmake.org/u/willem)
#### Post date: [December 9, 2022, 7:02am UTC](https://discourse.cmake.org/t/including-a-cmake-file/7034/6 "2022-12-09T07:02:07Z")

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Dear Craig:

THanks for your quick reaction. I was specifically confused about chapter 34.2 (13th edition), where the example includes the line:

list(APPEND CMAKE\_MODULE\_PATH ${CMAKE\_CURRENT\_LIST\_DIR}/cmake)

and then loads a module with include(dependencies.cmake). Since that is the only module loaded in the example, I concluded that it would reside in the cmake subdirectory (since otherwise above line would be superfluous). Anyhow, your response clarifies- thanks!