Module Nx_io.Cache_dirSource

get_root ?getenv () returns the base cache directory for Raven.

The cache directory is resolved using the following priority order: 1. RAVEN_CACHE_ROOT environment variable (highest priority; absolute cache root) 2. XDG_CACHE_HOME environment variable (if RAVEN_CACHE_ROOT not set) 3. $HOME/.cache (fallback, default behavior)

The resolved path will be RAVEN_CACHE_ROOT or "XDG_CACHE_HOME or HOME/.cache/raven".

• parameter getenv

  optional environment lookup function (defaults to Sys.getenv_opt) to facilitate testing.

Environment Variables

• RAVEN_CACHE_ROOT: Custom cache directory root (overrides all other settings)
• XDG_CACHE_HOME: XDG Base Directory cache location (standard on Linux/Unix)
• HOME: User home directory (used for fallback cache location)

get_path_in_cache ?getenv ~scope name returns the cache directory path for a specific component.

Parameters

• scope: list of directory names forming the scope (e.g. ["datasets"], ["models"; "bert"])
• name: the specific name within that scope (e.g. "iris", "gpt2")

Returns

• the cache directory path, including trailing slash.

• parameter getenv

  optional environment lookup function (defaults to Sys.getenv_opt) to facilitate testing.

Examples

Getting cache directory for the iris dataset:

  let cache_dir = Nx_core.Cache_dir.get_path_in_cache ~scope:["datasets"] "iris" in
  (* With default environment: ~/.cache/raven/datasets/iris/ *)

Getting cache directory with custom root:

  let getenv var =
    if var = "RAVEN_CACHE_ROOT" then Some "/tmp/my-cache" else None
  in
  let cache_dir =
    Nx_core.Cache_dir.get_path_in_cache ~getenv ~scope:["models"] "bert-base-uncased"
  in
  (* Result: /tmp/my-cache/models/bert-base-uncased/ *)