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authorRichard Carlsson <[email protected]>2014-12-23 14:23:35 +0100
committerRichard Carlsson <[email protected]>2015-05-22 12:43:53 +0200
commite533ea29e80a641f247022f321a3bf1a1456c56e (patch)
tree2681e4a828e5393d1cc5c539efd5285b92419fa2 /lib/syntax_tools/examples/merl/lispc.erl
parent9a81b28598fadc44bf506354c9227e41aac786f6 (diff)
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Include Merl in Syntax Tools
Diffstat (limited to 'lib/syntax_tools/examples/merl/lispc.erl')
-rw-r--r--lib/syntax_tools/examples/merl/lispc.erl102
1 files changed, 102 insertions, 0 deletions
diff --git a/lib/syntax_tools/examples/merl/lispc.erl b/lib/syntax_tools/examples/merl/lispc.erl
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+++ b/lib/syntax_tools/examples/merl/lispc.erl
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+%% ---------------------------------------------------------------------
+%% Licensed under the Apache License, Version 2.0 (the "License"); you may
+%% not use this file except in compliance with the License. You may obtain
+%% a copy of the License at <http://www.apache.org/licenses/LICENSE-2.0>
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%%
+%% @author Richard Carlsson <[email protected]>
+%% @copyright 2012 Richard Carlsson
+%% @doc Lisp compiler in Erlang.
+
+-module(lispc).
+
+-export([eval/1]).
+
+-record(st, {}).
+
+-include("lisp_test.erl").
+
+-include("merl.hrl").
+
+eval(Lisp) ->
+ compile(Lisp, tmp),
+ tmp:eval().
+
+compile(Lisp, ModName) ->
+ {Code, _} = gen(Lisp, #st{}),
+ Main = ?Q(["() ->",
+ " __print = fun (S, Xs) -> io:format(S,Xs), [] end,",
+ " __apply = fun erlang:apply/2,",
+ " __plus = fun erlang:'+'/2,",
+ " __equal = fun lisp:equal/2,",
+ " __gt = fun lisp:gt/2,",
+ " __knot = fun lisp:knot/1,",
+ " __y = fun (F) ->",
+ " (fun (X) -> F(fun (Y) -> (X(X))(Y) end) end)",
+ " (fun (X) -> F(fun (Y) -> (X(X))(Y) end) end)",
+ " end,",
+ " _@Code"]),
+ Forms = merl_build:module_forms(
+ merl_build:add_function(true, eval, [Main],
+ merl_build:init_module(ModName))),
+ %% %% Write source to file for debugging
+ %% file:write_file(lists:concat([ModName, "_gen.erl"]),
+ %% erl_prettypr:format(erl_syntax:form_list(Forms),
+ %% [{paper,160},{ribbon,80}])),
+ merl:compile_and_load(Forms, [verbose]).
+
+var(Atom) ->
+ merl:var(list_to_atom("__" ++ atom_to_list(Atom))).
+
+gen([lambda, Ps, B], St) when is_list(Ps) ->
+ case lists:all(fun is_atom/1, Ps) andalso
+ (length(Ps) =:= length(lists:usort(Ps))) of
+ true ->
+ Vars = [var(P) || P <- Ps],
+ {Body, St1} = gen(B, St),
+ {?Q("fun (_@Vars) -> _@Body end"), St1};
+ false ->
+ throw(bad_lambda)
+ end;
+gen([lambda | _], _) ->
+ throw(bad_lambda);
+gen([def, A, V, B], St) when is_atom(A) ->
+ Var = var(A),
+ {Val, St1} = gen(V, St),
+ {Body, St2} = gen(B, St1),
+ {?Q("(fun (_@Var) -> _@Body end)(_@Val)"), St2};
+gen([def | _], _) ->
+ throw(bad_def);
+gen([quote, A], St) ->
+ {merl:term(A), St};
+gen([quote | _], _) ->
+ throw(bad_quote);
+gen([iff, X, A, B], St) ->
+ {Cond, St1} = gen(X, St),
+ {True, St2} = gen(A, St1),
+ {False, St3} = gen(B, St2),
+ {?Q(["case _@Cond of",
+ " [] -> _@False;",
+ " _ -> _@True",
+ "end"]),
+ St3};
+gen([do], _) ->
+ throw(bad_do);
+gen([do | As], St0) ->
+ {Body, St1} = lists:mapfoldl(fun gen/2, St0, As),
+ {?Q("begin _@Body end"), St1};
+gen([list | As], St0) ->
+ {Elem, St1} = lists:mapfoldl(fun gen/2, St0, As),
+ {?Q("[ _@Elem ]"), St1};
+gen([_|_]=L, St) ->
+ {[F | As], St1} = lists:mapfoldl(fun gen/2, St, L),
+ {?Q("((_@F)(_@As))"), St1};
+gen(A, St) when is_atom(A) ->
+ {var(A), St};
+gen(C, St) ->
+ {merl:term(C), St}.