Ad notation: just an idea as "food for thoughts" for an alternate, "symbol 
free" notation: what
about if making the variable reference feature available via the VAR()-BIF? 
This idea would allow a
second argument "R" (for "reference") in the VAR()-BIF, which will return the 
VariableReference of
the supplied variable.

Hence instead of writing:

    a = 123
    call foo &a
    say a  -- displays "124"

    ::routine foo
      use arg &someVariable

      someVariable += 1
      return

one would code:

    a = 123
    call foo var(a,"reference")
    say a  -- displays "124"

    ::routine foo
      use arg refVar 
      someVariable=var(refVar,"r")

      someVariable += 1 
      return

As it may be expected that the variable reference is not needed as often in 
Rexx/ooRexx as in a
C-based language, one may forgo a proper symbol operator for this quite 
interesting functionality.

---rony

On 13.04.2018 11:30, Rony G. Flatscher wrote:
> There are at least two aspects for me: one is the functionality, one is the 
> notation.
>
>   * The functionality aspect is a generalization of  "expose objvar" in 
> method routines, now made
>     available in general. Therefore it could be used e.g. in ooRexx routine 
> packages where closely
>     related routines can be coupled efficiently via the variable references 
> or multiple variables
>     can be updated directly hence foregoing the need to process return values 
> to assign them to
>     the variables in question and the like ...
>
>   * Ad notation: there is a big difference between Rexx and Object Rexx from 
> day one. Object Rexx
>     introduced the tilde (~) and colons (in message names to indicate in 
> which superclass to start
>     resolution of the method) and double-colons (to clearly indicate the 
> boundaries of directives
>     that get preprocessed by the interpreter). And yes, initially they looked 
> a little bit alien
>     vis-a-vis to classic Rexx, but what is also observable, after a while (to 
> get accustomed to
>     them) they have been making quite a lot of sense in Object Rexx, and 
> indeed make the new
>     Object Rexx concepts clearly, explicitly visible.
>     Since 20 years there has been no other "alien" character been introduced 
> into the Object Rexx
>     language, where "alien" relates to classic Rexx. I recall "&[&]" use in 
> EXEC and in the C
>     language.
>     Using any symbol for the purpose of getting a reference to a variable 
> seems to be o.k. as the
>     operator needs to be explained anyway. My students for instance have 
> usually no preset concept
>     to "&", so that symbol is as fine as any other for them. Those who know 
> C/C++ have probably no
>     problem whatsoever to conceive the meaning immediately (learning that in 
> ooRexx it would not
>     be a memory address but a reference that gets returned). Whether EXEC 
> programmers minds have
>     been carved in stone such that they cannot conceive the meaning, well, I 
> do not know how they
>     would perceive that. But then, there is no need for them to use that 
> feature (or any of the
>     many other cool features of ooRexx), if they only have a need for the 
> classic Rexx features.
>
> The examples that Rick showed can be taught easily and using the operator in 
> both places
> (assignment expressions and USE ARG expressions) looks intuitive i.e. easily 
> explainable.
>
> I would like to experiment, "play around", explore with it ASAP (hopefully 
> being able to do so by
> early next week), also testing teaching it to the uninitiated to be able to 
> assess that aspect as
> well.
>
> ---rony

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