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kotlinlang

You can use it that way, but you don’t actually invoke the caller, so I don’t see the point in extending the `Date` class

eeeh no sorry intent is to set calendar at the extended day :slightly_smiling_face: so I guess i need to keep `this` referenco for the original date and can not do lambda right?

can you give us an example of input/output should be when you call that function?

I would say this is the way.. I mean I always can do in java way but want to d oin right kotlin way :slightly_smiling_face:

```fun Date.add(calendarUnit: Int, amount:Int): Date = let{
    val calendar = java.util.Calendar.getInstance()
    calendar.time=this
    calendar.add(calendarUnit,amount)
    return calendar.time
}```

inside the `let`, the date is both `this` and `it`, but its fine like that

I meant..  as I wanted it as extension, I need reference to date as `this`..  but i liked to get callendar into lambda as `it` but i probably overcomplicate ...

You could do ```
fun Date.add(calendarUnit: Int, amount: Int) {
  return java.util.Calendar.getInstance().apply{
      time = this
      add(calendarUnit, amount)
    }.time
}
```

Although, I don’t know that it’s necessarily easier to read :thinking_face:

hmm probaly so... i left it as 
```
fun Date.add(calendarUnit: Int, amount:Int): Date = let{
    val calendar = java.util.Calendar.getInstance()
    calendar.time=this
    calendar.add(calendarUnit,amount)
    return calendar.time
}
```

I have to say, `let` isn’t giving you any special functionality there. It’s essentially taking up space. You’re not even invoking `it`, which is the default binding it provides. You can just remove the `= let` and it functions precisely the same.

ok not want to prolongate the pain :slightly_smiling_face: but while getting my way to apply run witht etc... i thought even this as possibly propriate 
```
fun Date.add(calendarUnit: Int, amount:Int):Date =
        Calendar.getInstance().let {
            it.time=this
            it.add(calendarUnit,amount)
            it.time
        }
```