[Octave-bug-tracker] [bug #58953] Error with 'end' in index expression with nested function calls

[John W. Eaton]

Follow-up Comment #26, bug #58953 (project octave):

OK, I think understand now.

So, when evaluating obj.X(end), we don't need to look up fields/properties of
obj to check whether X is a property or method and then do different things
depending on that result (because normally, END would not be valid in a call
to a function).

Instead, we just call subsref for the obj.X part and END will apply to the
result of that, whatever it is.  And that subsref evaluation may fail if, for
example, it actually determines that X is a method that requires arguments. 
If you change your subsref method to be


  function r = subsref(obj,S)
      fprintf('-----------------\n')
      S.type
      S.subs
      fprintf('-----------------\n')
if (numel (S) == 1 && strcmp (S(1).type, '.') && strcmp (S(1).subs,
'methodA'))
  error ('methodA called without arguments!');
end
      r = ones(1,3);


and then execute


obj=myclass(1:5)
obj.methodA (end)


do you see the error "methodA called without arguments!" or something else?

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