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?

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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