feat(frontends/lean): add parser_config environment extension

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>

src/frontends/lean/CMakeLists.txt

@@ -1,4 +1,4 @@
 add_library(lean_frontend register_module.cpp token_table.cpp
-scanner.cpp parse_table.cpp)
+scanner.cpp parse_table.cpp parser_config.cpp)
 
 target_link_libraries(lean_frontend ${LEAN_LIBS})

src/frontends/lean/parser_config.cpp

@@ -0,0 +1,66 @@
+/*
+Copyright (c) 2014 Microsoft Corporation. All rights reserved.
+Released under Apache 2.0 license as described in the file LICENSE.
+
+Author: Leonardo de Moura
+*/
+#include "frontends/lean/parser_config.h"
+
+namespace lean {
+struct parser_ext : public environment_extension {
+    // Configuration for a Pratt's parser
+    token_table m_tokens;
+    parse_table m_nud;
+    parse_table m_led;
+};
+
+struct parser_ext_reg {
+    unsigned m_ext_id;
+    parser_ext_reg() { m_ext_id = environment::register_extension(std::make_shared<parser_ext>()); }
+};
+static parser_ext_reg g_ext;
+static parser_ext const & get_extension(environment const & env) {
+    return static_cast<parser_ext const &>(env.get_extension(g_ext.m_ext_id));
+}
+static environment update(environment const & env, parser_ext const & ext) {
+    return env.update(g_ext.m_ext_id, std::make_shared<parser_ext>(ext));
+}
+
+token_table const & get_token_table(environment const & env) {
+    return get_extension(env).m_tokens;
+}
+
+parse_table const & get_nud_parse_table(environment const & env) {
+    return get_extension(env).m_nud;
+}
+
+parse_table const & get_led_parse_table(environment const & env) {
+    return get_extension(env).m_led;
+}
+
+environment update_token_table(environment const & env, token_table const & t) {
+    parser_ext ext = get_extension(env);
+    ext.m_tokens = t;
+    return update(env, ext);
+}
+
+environment update_nud_parse_table(environment const & env, parse_table const & t) {
+    parser_ext ext = get_extension(env);
+    ext.m_nud = t;
+    return update(env, ext);
+}
+
+environment update_led_parse_table(environment const & env, parse_table const & t) {
+    parser_ext ext = get_extension(env);
+    ext.m_led = t;
+    return update(env, ext);
+}
+
+environment update_parse_config(environment const & env, token_table const & tk, parse_table const & nud, parse_table const & led) {
+    parser_ext ext = get_extension(env);
+    ext.m_tokens = tk;
+    ext.m_nud    = nud;
+    ext.m_led    = led;
+    return update(env, ext);
+}
+}

src/frontends/lean/parser_config.h

@@ -0,0 +1,21 @@
+/*
+Copyright (c) 2014 Microsoft Corporation. All rights reserved.
+Released under Apache 2.0 license as described in the file LICENSE.
+
+Author: Leonardo de Moura
+*/
+#pragma once
+#include "kernel/environment.h"
+#include "frontends/lean/token_table.h"
+#include "frontends/lean/parse_table.h"
+
+namespace lean {
+token_table const & get_token_table(environment const & env);
+parse_table const & get_nud_parse_table(environment const & env);
+parse_table const & get_led_parse_table(environment const & env);
+
+environment update_token_table(environment const & env, token_table const & t);
+environment update_nud_parse_table(environment const & env, parse_table const & t);
+environment update_led_parse_table(environment const & env, parse_table const & t);
+environment update_parse_config(environment const & env, token_table const & tk, parse_table const & nud, parse_table const & led);
+}