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+===== Ideas for Fortran improvements =====
+==== Default values for optional arguments ====
+Currently, default values for optional arguments have to be handled like this:
+<code fortran>
+subroutine test(n_arg)
+  integer, intent(in), optional :: n_arg ! Default is 10
+  integer :: n_used
+  if (present(n_arg)) then
+     n_used = n_arg
+  else
+     n_used = 10
+  end if
+  ... ! Do something with n_used
+</code>
+It would be more convenient if this was possible:
+<code fortran>
+subroutine test(n)
+  integer, intent(in), optional :: n = 10 ! Default is 10
+  ...
+</code>
+Note that this syntax is also used to initialize variables with the 'save'
+attribute, but since that attribute does not apply to optional arguments it
+should be fine.
+==== Multi-dimensional vector indexing ====
+Currently, you can use vectors for indexing. Given three vectors **a, b, c** of equal length, you can e.g. do:
+<code fortran>
+a(b(:)) = c
+</code>
+which is the same as writing
+<code fortran>
+a(b(1)) = c(1)
+a(b(2)) = c(2)
+...
+</code>
+Now suppose we have a matrix **D**, and we have an index vector **ix**. Then
+there is currently now way to do
+<code fortran>
+ix = [1, 1]
+D(ix) = 0 ! Illegal
+</code>
+Instead, you have to write
+<code fortran>
+ix = [1, 1]
+D(ix(1), ix(2)) = 0 ! Correct
+</code>
+I suggest to add the following syntax rule: if a /n/-dimensional array is
+indexed by a single vector of length /n/, then automatically treat is as an
+index, so that both the above code snippets behave the same.
+==== Passing arrays of unknown dimension ====
+It would be great if something like this was supported:
+<code fortran>
+subroutine example(my_array, ndim)
+  integer, intent(in) :: ndim
+  real, intent(in)    :: my_array(dim=ndim)
+  integer             :: nx(ndim)
+  nx = shape(my_array)
+  ...
+end subroutine example
+</code>

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