No way to set `ProgramGenerator::Function::outputArraySizeSource` from snippet files

[cmdrf]

ProgramGenerator::Function::outputArraySizeSource is used to determine the array size of the return value of a function. In this example, lightDirectionArray is supposed to inherit the array size from lightPositionArray:

vertex
vec3[] lightDirectionArray(vec4[] lightPositionArray, vec4 vertexPosition, mat4 modelViewMatrix)
{
	for(int i = 0; i < lightDirectionArray.length(); i++)
	{
		lightDirectionArray[i] = -normalize(lightPositionArray[i].xyz - (modelMatrix * vertexPosition).xyz);
	}
}

You can do that in C++ with

lightDirectionArray.outputArraySizeSource = "lightPositionArray"_H;

but not from the text file.