For a non-empty list l, unflatten l is Some lid where lid is the long identifier created by concatenating the elements of l with Ldot. unflatten [] is None.

head lid returns the leftmost part of lid, e.g., given String.Map.empty, returns String.

• raises Assert_failure

  if encounters Lapply

This function is broken on identifiers that are not just "Word.Word.word"; for example, it returns incorrect results on infix operators and extended module paths.

If you want to generate long identifiers that are a list of dot-separated identifiers, the function unflatten is safer and faster. unflatten is available since OCaml 4.06.0.

If you want to parse any identifier correctly, use the long-identifiers functions from the Parse module, in particular Parse.longident. They are available since OCaml 4.11, and also provide proper input-location support.

if li', b = keep_suffix li then:

• the prefix of li' is a module path
• b = false iff li' = li. Corollary: b = true if li is a label access (i.e. li = X.Y.z.Foo.Bar...)