%%% vim:ts=2:sw=2:et
%%%-----------------------------------------------------------------------------
%%% @doc Erlang pipeline parse transform
%%%
%%% This transform implements a parser syntax extension that enables application
%%% of cascading function calls using the `/' operator.
%%%
%%% In the `LHS / RHS / ... Last.' notation, the result of evaluation of the LHS
%%% expression is passed as an argument to the RHS expression. This process
%%% continues until the `Last' expression is evaluated.  The head element of the
%%% pipeline must be either a term to which the arithmetic division `/` operator
%%% cannot apply (i.e. not integers, floats, functions), or if you need to pass
%%% integer(s) or float(s), wrap them in a list brackets.
%%%
%%% This transfor is inspired by the similar functionality in Linux (i.e. `|'
%%% pipe) and Elixir (`|>' pipe).
%%%
%%% When using this as a parse transform, include the `{parse_transform,erlpipe}'
%%% compiler option.
%%%
%%% The following examples illustrate the work of the transform, in which:
%%% ```
%%% test1(A)   -> [A]   / fun1 / mod:fun2 / fun3.
%%% test2(A,B) -> [A,B] / fun4 / fun5() / io:format("~p\n", [_]).
%%% '''
%%% will be transformed to:
%%% ```
%%% test1(A)   -> fun3(mod:fun2(fun1(A))).
%%% test2(A,B) -> io:format("~p\n", [fun5(fun4(A,B))]).
%%% '''
%%%
%%% Similarly to Elixir, a special `tap/2' function is implemented, which
%%% passes the given argument to an anonymous function, returning the argument
%%% itself. The following:
%%% ```
%%% f(A) -> A+1.
%%% ...
%%% test_tap() ->
%%%   [10] / tap(f)
%%%        / tap(fun f/1)
%%%        / tap(fun(I) -> I+1 end).
%%% '''
%%% is equivalent to:
%%% ```
%%% ...
%%% test_tap() ->
%%%   begin
%%%     f(10),
%%%     begin
%%%       f(10),
%%%       begin
%%%         (fun(I) -> I end)(10)
%%%         10
%%%       end
%%%     end
%%%   end.
%%% '''
%%%
%%% For debugging the AST of the resulting transform, pass the following
%%% options to the `erlc' compiler:
%%% <dl>
%%% <li>`-Derlpipe_orig' - print the original AST before the transform</li>
%%% <li>`-Derlpipe_ast'  - print the transformed AST</li>
%%% <li>`-Derlpipe_src'  - print the resulting source code after the transform</li>
%%% </dl>
%%%
%%% @author Serge Aleynikov <saleyn(at)gmail(dot)com>
%%% @end
%%%-----------------------------------------------------------------------------
%%% Copyright (c) 2021 Serge Aleynikov
%%%
%%% Permission is hereby granted, free of charge, to any person
%%% obtaining a copy of this software and associated documentation
%%% files (the "Software"), to deal in the Software without restriction,
%%% including without limitation the rights to use, copy, modify, merge,
%%% publish, distribute, sublicense, and/or sell copies of the Software,
%%% and to permit persons to whom the Software is furnished to do
%%% so, subject to the following conditions:
%%%
%%% The above copyright notice and this permission notice shall be included
%%% in all copies or substantial portions of the Software.
%%%
%%% THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
%%% EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
%%% MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
%%% IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
%%% CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
%%% TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
%%% SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
%%%-----------------------------------------------------------------------------
-module(tmp).

-export([parse_transform/2]).
-import(etran_util, [transform/2]).

-define(OP, '/').

%% @doc parse_transform entry point
parse_transform(AST, Options) ->
  etran_util:apply_transform(?MODULE, fun replace/1, AST, Options).

replace(_Exp) ->
  continue.