To pass an argument with no value to CMake, you can simply specify the argument without providing a value. For example, if you have a CMake variable named "MY_FLAG" that can be set to enable a certain feature, you can pass it without a value like this: "-DMY_FLAG".
In CMake, arguments without values are treated as being set to "ON" by default. This means that if you pass "-DMY_FLAG" without a value, it will be interpreted as setting "MY_FLAG" to "ON". Alternatively, you can explicitly set it to "ON" by passing "-DMY_FLAG=ON".
If you want to explicitly disable a flag that can be toggled on or off, you can pass "-DMY_FLAG=OFF". This will set "MY_FLAG" to "OFF" and disable the feature associated with it.
Overall, passing an argument with no value to CMake is a simple and straightforward process that allows you to enable or disable features in your CMake configuration.
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What is the difference between a null argument and an empty argument in cmake?
In CMake, a null argument refers to a variable that has not been defined or assigned any value. This means that the variable does not exist and cannot be used in the CMake script.
On the other hand, an empty argument refers to a variable that has been defined but has no value assigned to it. This means that the variable exists in the CMake script, but it is empty or contains no data.
In summary, a null argument does not exist in the CMake script, while an empty argument exists but has no value assigned to it.
How to declare an empty argument in a cmake script?
To declare an empty argument in a CMake script, you can use the following syntax:
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function(my_function ARG1) if(DEFINED ARG1) message("Argument 1: ${ARG1}") else() message("Argument 1 is empty") endif() endfunction() # Call the function with an empty argument my_function() |
In this example, the my_function function takes one argument ARG1. If the argument is not defined, it will be considered empty and the script will output "Argument 1 is empty".
What is the default behavior of cmake when an argument has no value?
By default, when an argument has no value in CMake, it is treated as a "true" value. This means that if an argument is passed to CMake without a value, it is considered to be set to true by default.
