Write a few docs

src/geef.erl

@@ -1,3 +1,6 @@
+%%% @private
+%%% NIF functions, not to be used directly.
+
 -module(geef).
 -export([hex_to_raw/1, reference_list/1,
 	 reference_to_id/2, reference_glob/2, reference_lookup/2, reference_resolve/1,

src/geef_oid.erl

@@ -1,3 +1,4 @@
+%%% @doc Dealing with object names
 -module(geef_oid).
 
 -ifdef(TEST).
@@ -8,12 +9,13 @@
 
 -export([parse/1, fmt/1]).
 
+%% @doc Get the hex-encoded hash
 -spec fmt(oid()) -> binary().
 fmt(#oid{oid=Oid}) ->
     geef:oid_fmt(Oid).
 
-
--spec parse(binary()) -> oid().
+%% @doc Parse an iolist as a hash
+-spec parse(iolist()) -> oid().
 parse(Sha) ->
     Oid = geef:oid_parse(Sha),
     #oid{oid=Oid}.

src/geef_repo.erl

@@ -4,14 +4,18 @@
 
 -include("geef_records.hrl").
 
+%% @doc The repository's git-dir path
 -spec path(repo()) -> binary().
 path(#repo{handle=Handle}) ->
     geef:repository_get_path(Handle).
 
+%% @doc The repository's worktree path
 -spec workdir(repo()) -> binary().
 workdir(#repo{handle=Handle}) ->
     geef:repository_get_workdir(Handle).
 
+%% @doc The repository's current object database. This encompasses all
+%% the configured backends.
 -spec odb(repo()) -> {ok, odb} | {error, term}.
 odb(#repo{handle=Handle}) ->
     case geef:repository_get_odb(Handle) of
@@ -21,18 +25,23 @@ odb(#repo{handle=Handle}) ->
 	    Other
     end.
 
+%% @doc Whether the repository is bare
 -spec is_bare(repo()) -> boolean().
 is_bare(#repo{handle=Handle}) ->
     geef:repository_is_bare(Handle).
 
+%% @doc List of references in the repository.
 -spec references(repo()) -> [binary()].
 references(#repo{handle=Handle}) ->
     geef:reference_list(Handle).
 
+%% @doc Discover a repository's path from a path contained inside it
 -spec discover(iolist()) -> {ok, binary()} | error | {error, term()}.
 discover(Path) ->
     geef:repository_discover(Path).
 
+%% @doc Open an existing repository. Path must point to the git-dir or
+%% worktree
 -spec open(iolist()) -> {ok, repo()} | {error, term()}.
 open(Path) ->
     case geef:repository_open(Path) of
@@ -42,6 +51,7 @@ open(Path) ->
 	    Other
     end.
 
+%% @doc Initialize a new repository
 -spec init(iolist(), boolean()) -> {ok, repo()} | {error, term()}.
 init(Path, Bare) ->
     case geef:repository_init(Path, Bare) of