diff --git a/PROPOSAL.md b/PROPOSAL.md
new file mode 100644
index 0000000..bbdc424
--- /dev/null
+++ b/PROPOSAL.md
@@ -0,0 +1,59 @@
+
+### encoding user's data
+
+You can encode your data to toml format.
+
+```cpp
+const toml::value integer(1);
+const toml::value array{3.1, 3.14, 3.141, 3.1415};
+const toml::value table{{"answer", 42}, {"pi", 3.14}, {"string", "foobar"}};
+
+std::cout << toml::format("integer", integer) << std::endl;
+std::cout << toml::format("array",   array)   << std::endl;
+std::cout << toml::format("table",   table)   << std::endl;
+```
+
+this program will output as below.
+
+```toml
+integer = 1
+array = [3.1, 3.14, 3.141, 3.1415]
+[table]
+answer = 42
+pi = 3.14
+string = "foobar"
+```
+
+Without key name, you can make string formatted as toml.
+
+```cpp
+const std::string integer_ = toml::format(integer); // "1"
+const std::string array_   = toml::format(array);   // "[3.1, 3.14, 3.141, 3.1415]"
+const std::string table_   = toml::format(table);   // "answer = 42\npi=3.14\nstring=foobar"
+```
+
+### inlinize
+
+You can make `toml::Table` inline.
+
+```cpp
+const toml::value table{{"answer", 42}, {"pi", 3.14}, {"string", "foobar"}};
+// if the inline-table format length is less than 80, the table will be inlined
+std::cout << toml::format("table", table, toml::make_inline(80)) << std::endl;
+// In any case, the table will be inlined.
+std::cout << toml::format("table", table, toml::forceinline) << std::endl;
+```
+
+```toml
+table = {answer = 42, pi = 3.14, string = "foobar"}
+```
+
+And there are some stream manipulators for toml format.
+
+```cpp
+const toml::value table{{"answer", 42}, {"pi", 3.14}, {"string", "foobar"}};
+// if the inline-table format length is less than 80, the table will be inlined
+std::cout << toml::make_inline(80) << table << std::endl;
+// In any case, the table will be inlined.
+std::cout << toml::forceinline << table << std::endl;
+```
diff --git a/README.md b/README.md
index 989da2c..3f91625 100644
--- a/README.md
+++ b/README.md
@@ -42,8 +42,7 @@ If there are syntax error in the toml file,
 
 #### toml::get()
 
-Then you can obtain the various value from the `data` using `toml::get` function
-no matter what the value type is.
+Then you can obtain the various value from the `data` using `toml::get` function.
 
 ``` cpp
 const auto answer    = toml::get<std::int64_t>(data.at("answer"));
@@ -60,13 +59,20 @@ const auto vc  = toml::get<std::vector<int>>(data.at("numbers"));
 const auto ls  = toml::get<std::list<int>>(data.at("numbers"));
 const auto dq  = toml::get<std::deque<int>>(data.at("numbers"));
 // if size of data.at("numbers") is larger than 3, it will throw toml::type_error.
+// because std::array is not resizable.
 const auto ar  = toml::get<std::array<int, 3>>(data.at("numbers"));
 ```
 
 If the type you passed as a template parameter is incorrect,
 it will throw `toml::type_error`.
 
-#### value\_t and toml::value::type()
+``` cpp
+const auto wrong1 = toml::get<bool>(data.at("integer")); // exception thrown!
+const auto wrong2 = toml::get<float>(data.at("integer"));        // ditto
+const auto wrong3 = toml::get<toml::Datetime>(data.at("array")); // ditto
+```
+
+#### toml::value\_t
 
 When you don't know the exact type of toml-value, you can get `enum` type from
 `toml::value`.
@@ -79,10 +85,10 @@ std::vector<int> a;
 const auto t = data.at("something").type();
 switch(t)
 {
-    case toml::value_t::Integer: i = toml::get<int>(data.at("something"));
-    case toml::value_t::Float  : d = toml::get<double>(data.at("something"));
-    case toml::value_t::String : s = toml::get<std::string>(data.at("something"));
-    case toml::value_t::Array  : a = toml::get<std::vector<int>>(data.at("something"));
+    case toml::value_t::Integer: i = toml::get<int>(data.at("something")); break;
+    case toml::value_t::Float  : d = toml::get<double>(data.at("something")); break;
+    case toml::value_t::String : s = toml::get<std::string>(data.at("something")); break;
+    case toml::value_t::Array  : a = toml::get<std::vector<int>>(data.at("something")); break;
     default : throw std::runtime_error("unexpected type : " + stringize(t));
 }
 ```