The callback argument passed to foreign import javascript interruptible functions is undocumented
Summary
Location of documentation issue: the GHC user's guide for FFI and the JavaScript Backend.
The JavaScript Backend will pass a callback function as extra last argument to the JavaScript function defined or referenced by a foreign import javascript interruptible
string. Such argument does not appear in the Haskell type signature of the function.
For more details and context: https://github.com/ghcjs/ghcjs-dom/pull/104#issuecomment-1945867928
Proposed improvements or changes
The semantics of the foreign import javascript interruptible
functions should be added the JavaScript Backend FFI documentation, together with a mention of the extra callback parameter and an example of how to use it in JavaScript code.
Environment
- GHC version used (if appropriate): 9.8.1