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Does the access method of a dependent property get called twice when the property is indexed into?

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I have a class with a dependent property z. The method get.z(obj) returns a vector. This:
y = myObj.z(end);
appears to call get.z twice! The profiler shows 2 calls from the parent function and the run time is twice the expected run time. On the other hand:
x = myObj.z;
y = x(end);
calls get.z once and cuts down run time by half. Is this the intended behavior?
  1 Comment
Walter Roberson
Walter Roberson on 13 Oct 2016
I speculate that one of the two is due to the "end", as it would need to find the size . This is just speculation on my part, though.

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Accepted Answer

Naor Movshovitz
Naor Movshovitz on 13 Oct 2016
Confirmed Walter's comment. Indeed the culprit is the keyword end. Here is minimal working example.
classdef Untitled
properties (Dependent)
x;
end
methods
function val = get.x(~)
fprintf('called\n')
val = [1,2,3];
end
end
end
>> obj = Untitled;
>> obj.x(2);
called
ans =
2
>> obj.x(end)
called
called
ans =
3
This behavior is mostly benign but occasionally troublesome, and easy to fix. I think this is a case for an m-lint message at least.

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