Test_interfaces.Directory_readerA directory reader is a Trait that is able to list all the entries contained in a directory in the file system.
The tag is used as a phantom type to characterize the nature of the specific provider that this library needs.
type 'a t = [> tag ] as 'a Provider.packedThis library can operate on any provider, as long as it implements at least the `Directory_reader capability.
val readdir : _ t -> path:Base.string -> Base.string Base.listThis function will result in calling the method readdir implemented by the provider.
val find_files_with_extension :
_ t ->
path:Base.string ->
ext:Base.string ->
Base.string Base.listThis function will result in calling the method readdir implemented by the provider, and then filtering the results to only keep the files with the given extension. This shows an example of a function that is implemented on top of a minimal interface furnished by a provider. Its implementation is shared across providers, since it lives in the implementation of this module.
module Provider_interface : sig ... endSuch abstraction will export a way for implementers (providers) to provide the implementation required by that interface. In Eio naming conventions, these modules are typically named Pi.