### Author:  [@daroxs95](https://discourse.cmake.org/u/daroxs95)
#### Post date: [December 6, 2020, 5:31pm UTC](https://discourse.cmake.org/t/help-passing-passing-empty-parameter-indirectly-to-externalproject-add/2307/1 "2020-12-06T17:31:35Z")
this code is not working currently(not deactivating the download step), if provided non empty string, it does treat it as the download command
```auto
set(FRESH_DOWNLOAD off CACHE BOOL "download a fresh copy of all dependencies")
include(ExternalProject)
if (NOT FRESH_DOWNLOAD)
# Define the variable to disable DOWNLOAD step
set(civ_DOWNLOAD DOWNLOAD_COMMAND "")
else()
# Define an empty variable.
# This actually can be omitted since absent variable is treated as empty.
set(civ_DOWNLOAD)
endif()
ExternalProject_Add(civ
SOURCE_DIR ${PROJECT_SOURCE_DIR}/test
BUILD_COMMAND ${MAKE_EXE}
BINARY_DIR "./bin"
INSTALL_COMMAND ""
GIT_REPOSITORY "https://github.com/test/test"
GIT_TAG "v1.0"
${civ_DOWNLOAD} # IMPORTANT: Do not use double quotes here.
CMAKE_ARGS
"-DTuberosumTools_DIR=${TUBEROSUMTOOLS_DIR}"
)
```
original question here
>
---
### Author:  [@ben.boeckel](https://discourse.cmake.org/u/ben.boeckel)
#### Post date: [December 6, 2020, 6:37pm UTC](https://discourse.cmake.org/t/help-passing-passing-empty-parameter-indirectly-to-externalproject-add/2307/2 "2020-12-06T18:37:02Z")
Passing empty strings is tough. For simplicity, I would recommend using a command of something like `true` (for Unix) or a similar command on Windows. It has a similar effect, but you don’t have to fight argument quoting rules.
---
### Author:  [@daroxs95](https://discourse.cmake.org/u/daroxs95)
#### Post date: [December 7, 2020, 4:45pm UTC](https://discourse.cmake.org/t/help-passing-passing-empty-parameter-indirectly-to-externalproject-add/2307/3 "2020-12-07T16:45:54Z")
Thanks, that is my currently solution, except i need the code to be crossplatform, so instead of `"true"` i am trying to use something like `"cd ."`, but i am really new to cmake, and not sure how to write it cause that way is not executed exactly like that, my guess is that cmake adds arguments. I am also new to `bash` and windows `cmd` so, no idea what alternative could use.
EDIT: i am using `dir` right now, not the best aproach though.
---
### Author:  [@ben.boeckel](https://discourse.cmake.org/u/ben.boeckel)
#### Post date: [December 7, 2020, 5:15pm UTC](https://discourse.cmake.org/t/help-passing-passing-empty-parameter-indirectly-to-externalproject-add/2307/4 "2020-12-07T17:15:45Z")
It might be easier to make the `GIT_` information conditional. That way, ExternalProject won’t know how to downoad it anyways.
---
### Author:  [@daroxs95](https://discourse.cmake.org/u/daroxs95)
#### Post date: [December 7, 2020, 11:41pm UTC](https://discourse.cmake.org/t/help-passing-passing-empty-parameter-indirectly-to-externalproject-add/2307/5 "2020-12-07T23:41:42Z")
You mean like the repo name? Never think in that, i will try it, thanks again.