nonlocal fails ?

[Richard Damon]

On 11/15/19 11:26 AM, Dennis Lee Bieber wrote:
> On Fri, 15 Nov 2019 12:56:02 +0100, "R.Wieser" <address at not.available>
> declaimed the following:
>
>> There are quite a number of languages where /every/ type of argument 
>> (including values) can be transfered "by reference".  Though some default to 
>> "by value", where others default to "by reference".
>>
> 	Yes -- and in those languages the concept of value vs reference is
> visible at the source code level. In C, everything is passed by value --
> and the programmer uses & to pass (by value) the address of the argument,
> and uses * in the called function to dereference that address back to the
> data item itself. C++ added reference arguments (where the & is used in the
> function declaration) in which the compiler automatically applies the
> "address" and "dereference" operations.

There are languages where pass by reference is the default and not explicit.

I remember in early FORTRAN being able to do something like this (its
been years since I have done this so syntax is probably a bit off)


PROCEDURE foo(i)

i = 2

return


then elsewhere you could do

foo(j)

and after that j is 2

you also could do

foo(1)

and after that if you did

j = 1

then now j might have the value 2 as the constant 1 was changed to the
value 2 (this can cause great confusion)

later I believe they added the ability to specify by value and by
reference, and you weren't allowed to pass constants by reference,

-- 
Richard Damon