if install path exists .., it cannot be resolved correctly.

[Freed-Wu]

Such as

option("xmake-platlib")
set_default("/../platlib")
target("main")
add_installfiles("src/example/*.py", {prefixdir= "$(xmake-platlib)/example"}) 

$ xmake install -o/tmp/tmp6np2qz78/data

installing c ..
installing c to /tmp/tmp6np2qz78/data ..
error: install failed, cannot copy file /dev/shm/xmake-python/tests/examples/cython/src/example/py.py to /tmp/tmp6np2qz78/data/../platlib/example/py.py, No such file or directory
In [1]: !ls /dev/shm/xmake-python/tests/examples/cython/src/example/py.py
/dev/shm/xmake-python/tests/examples/cython/src/example/py.py
In [2]: !ls /tmp/tmp6np2qz78/
data  metadata  null  platlib  xmake.lua

xmake can install file to /tmp/tmp6np2qz78/platlib/example/py.py, not /tmp/tmp6np2qz78/data/../platlib/example/py.py.

[waruqi]

prefixdir does not support $(var)