设置文件权限🔗

由于相关 API 不够直观，设置文件权限较为复杂。下面是一个示例，展示如何用 Lean4 参考手册这里提供的 IO.AccessRight、IO.FileRight 和 IO.setAccessRights API 为一个文件路径设置文件权限。

def setFilePermissions (path : System.FilePath) : 
    IO Unit := do
  -- Define specific access rights
  let rw : IO.AccessRight := 
    { read := true, write := true, execution := false } 
  let rOnly : IO.AccessRight := 
    { read := true, write := false, execution := false }

  -- Construct the FileRight structure
  -- Setting User to RW, Group to R, and Other to R
  let myRights : IO.FileRight := {
    user  := rw,
    group := rOnly,
    other := rOnly
  }

  -- Apply the rights to the file
  IO.setAccessRights path myRights
  IO.println s!"Access rights for {path} have been updated."