Metaprogramming: Introspection
元编程：内省（xǐng）
Ruby code:
class Greeting
def initialize text
@text = text
end
def welcome
@text
end
end
my_object = Greeting.new "Hello"
puts my_object.welcome
puts
puts my_object.class
puts
puts my_object.class.instance_methods false
puts
puts my_object.instance_variables
ECMAScript/JavaScript Code:
"use strict";
class Greeting {
constructor(text) {
this.text = text;
}
welcome() {
return this.text;
}
}
var my_object = new Greeting("Hello");
console.log(my_object.welcome());
console.log('');
console.log(my_object.constructor);
console.log('');
for (var m in my_object) {
console.log(m);
}
console.log('');
console.log(my_object);
CoffeeScript code:
class Greeting
constructor: (text) ->
@text = text
welcome: ->
@text
my_object = new Greeting "Hello"
console.log my_object.welcome()
console.log ''
console.log my_object.constructor
console.log ''
console.log m for m of my_object
console.log ''
console.log my_object