如何将os.iorun函数返回的结果作为add_requires的参数？

[wangyexiang]

大家好，我是新接触xmake，想请教一个问题，如何将os.iorun函数返回的结果作为add_requires的参数?
我期望的代码如下：

local torch_install_prefix = os.iorun("python -c 'import torch;print(torch.utils.cmake_prefix_path)'")
add_requires("cmake::Torch",{system = true, configs = {envs = {CMAKE_PREFIX_PATH = torch_install_prefix}}})

但是会报错：error: .\xmake.lua:6: field 'iorun' is not callable (a nil value)
如果我将上面的代码放在before_build中，即：

before_build(function (target)
    local torch_install_prefix = os.iorun("python -c 'import torch;print(torch.utils.cmake_prefix_path)'")
    add_requires("cmake::Torch",{system = true, 
                                configs = {envs = {CMAKE_PREFIX_PATH = torch_install_prefix}}
                                })
end)

它又会报错：error: global 'add_requires' is not callable (a nil value)
请问一下，有办法将torch_install_prefix作为add_requires的参数吗？

[waruqi]

不支持，不要乱用。。另外 xmake-repo 仓库有 torch 包，可以直接用