Expansion_context.Baseval code_path : t -> Code_path.tReturn the code path for the given context In Driver, Deriving and Extension, the context is initialized so that the file_path component of the code_path is determined from the first location found in the input AST. That means that:
val input_name : t -> stringReturn the input name for the given context. In Driver, Deriving and Extension, the context argument is initialized so that the input_name matches the input filename passed to the driver on the command line. That means that:
"_none_" when using Driver.map_structure or Driver.map_signatureval tool_name : t -> stringCan be used within a ppx preprocessor to know which tool is calling it "ocamlc", "ocamlopt", "ocamldep", "ocaml", ... .