README.md in tspec-0.2.0 vs README.md in tspec-0.3.0

@@ -35,10 +35,13 @@
 require 'tspec'
 
 def echo(str)
   puts str
 end.receive(str: String)
+
+echo('hello world') #=> ok
+echo(123)           #=> TSpec::ArgumentTypeError
 ```
 
 You can specify multiple type, too.
 
 ```ruby
@@ -46,12 +49,13 @@
 
 def echo(val)
   puts val
 end.receive(val: [String, Float])
 
-echo('hello')
-echo(3.14)
+echo('hello')  #=> ok
+echo(3.14)     #=> ok
+echo(123)      #=> TSpec::ArgumentTypeError
 ```
 
 If single method argument is given, you can skip keyword.
 
 ```ruby
@@ -59,11 +63,12 @@
 
 def join_array(arr)
   arr.join(' ')
 end.receive([String])
 
-puts join_array(%w(hello world))
+puts join_array(%w(hello world)) #=> ok
+puts join_array([1,2,3])         #=> TSpec::ArgumentTypeError
 ```
 
 You can specify Array content type, although it may seem strange.
 
 ```ruby
@@ -71,11 +76,12 @@
 
 def receive_string_array(arr)
   arr.join
 end.receive(arr: [[String]])
 
-puts receive_string_array(['hello', 'world'])
+puts receive_string_array(['hello', 'world']) #=> ok
+puts receive_string_array([:hello, :world])   #=> TSpec::ArgumentTypeError
 ```
 
 
 ### return
 
@@ -85,10 +91,17 @@
 require 'tspec'
 
 def message
   'hello world'
 end.return(String)
+
+def dummy_message
+  'hello world'
+end.return(Symbol)
+
+puts message        #=> ok
+puts dummy_message  #=> TSpec::ReturnValueTypeError
 ```
 
 You can specify multiple return value, too.
 
 ```ruby
@@ -124,18 +137,17 @@
 
 def string2symbol(str)
   str.to_sym
 end.receive(str: String).return(Symbol)
 
-p string2symbol('hello') #=> :hello
-p string2symbol(123)     #=> TSpec::ArgumentTypeError
+p string2symbol('hello')  #=> :hello
+p string2symbol(123)      #=> TSpec::ArgumentTypeError
 ```
 
 ## Contributing
 
 Bug reports and pull requests are welcome on GitHub at https://github.com/siman-man/tspec. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the [Contributor Covenant](http://contributor-covenant.org) code of conduct.
 
 
 ## License
 
 The gem is available under the terms of the [MIT License](http://opensource.org/licenses/MIT).
-