Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Welcome To Ask or Share your Answers For Others

Categories

0 votes
1.1k views
in Technique[技术] by (71.8m points)

oop - Private members in CoffeeScript?

Does somebody know how to make private, non-static members in CoffeeScript? Currently I'm doing this, which just uses a public variable starting with an underscore to clarify that it shouldn't be used outside of the class:

class Thing extends EventEmitter
  constructor: (@_name) ->

  getName: -> @_name

Putting the variable in the class makes it a static member, but how can I make it non-static? Is it even possible without getting "fancy"?

See Question&Answers more detail:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Reply

0 votes
by (71.8m points)

classes are just functions so they create scopes. everything defined inside this scope won't be visible from the outside.

class Foo
  # this will be our private method. it is invisible
  # outside of the current scope
  foo = -> "foo"

  # this will be our public method.
  # note that it is defined with ':' and not '='
  # '=' creates a *local* variable
  # : adds a property to the class prototype
  bar: -> foo()

c = new Foo

# this will return "foo"
c.bar()

# this will crash
c.foo

coffeescript compiles this into the following:

(function() {
  var Foo, c;

  Foo = (function() {
    var foo;

    function Foo() {}

    foo = function() {
      return "foo";
    };

    Foo.prototype.bar = function() {
      return foo();
    };

    return Foo;

  })();

  c = new Foo;

  c.bar();

  c.foo();

}).call(this);

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
OGeek|极客中国-欢迎来到极客的世界,一个免费开放的程序员编程交流平台!开放,进步,分享!让技术改变生活,让极客改变未来! Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Click Here to Ask a Question

...