Javascript delegate - Stack Overflow

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I have the following the code

function createDelegate(object, method)
{
    var shim =  function()
    {                   
         method.apply(object, arguments);
    }
    return shim;
}


this.test = 3;   
var pAction = {to: this.test}
this.tmp = createDelegate(this, function()
{
              print("in: " + pAction.to); 
              return pAction.to;
});
print("out: " + this.tmp());

But for some reason I get the following result

in: 3
out: undefined

Anyone knows the reason for this?

I have the following the code

function createDelegate(object, method)
{
    var shim =  function()
    {                   
         method.apply(object, arguments);
    }
    return shim;
}


this.test = 3;   
var pAction = {to: this.test}
this.tmp = createDelegate(this, function()
{
              print("in: " + pAction.to); 
              return pAction.to;
});
print("out: " + this.tmp());

But for some reason I get the following result

in: 3
out: undefined

Anyone knows the reason for this?

• javascript
• delegates

Share Improve this question Follow edited Sep 29, 2011 at 10:22 AmGates 2,1231616 silver badges2929 bronze badges asked Sep 29, 2011 at 10:11 JMCamposJMCampos 65311 gold badge1010 silver badges2424 bronze badges 3

• 1 FWIW, your code basically tries to emulate the ES5 .bind() method. Have a look at the MDN documentation to see their implementation. – Felix Kling Commented Sep 29, 2011 at 10:24
• Wat output do you expect in "out" ? – AmGates Commented Sep 29, 2011 at 10:31
• Thanks Felix Kling. Gonna take a look at it. – JMCampos Commented Sep 29, 2011 at 10:42

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1 Answer 1

Sorted by: Reset to default 6

When you create the delegated function you must return the result of the old function:

function createDelegate(object, method)
{
 var shim =  function()
 {                  
    return method.apply(object, arguments);
 }
 return shim;
}

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