[fpc-devel] Proposal: In-out-parameters

["Vinzent Höfler"]

_-jane-_ at web.de:

> You wrote 2010-08-09 [Proposal: Enhanced replacement for assignment
> operators]:
> > BTW.: are there "inout" Parameters that are set on entry and written on 
> > exit of a procedure, but not modified during the course of the procedure
> ?
> 
> One could propose a new kinds of parameter transmission: copy-in-copy-out
> and copy-out.
> In Ada this is a valid method to transmit scalar parameters (as a
> alternative to reference ("var") parameters).
> See http://archive.adaic.com/standards/83lrm/html/lrm-06-02.html

You should at least have used the 1995 version. Ada83 is pretty outdated, even here[tm], considering that Ada2005 compilers are available for about five years now. :D

<http://www.adahome.com/rm95/rm9x-06-02.html>

> These kinds of parameter transmission can be used for properties.

Well, it would involve a function call to the getter upon entry and another one to the setter upon exit. So it would be much more than just a by-copy transfer (which usually is nothing more than just using a register holding the value instead of a pointer to the actual memory location).


Vinzent.

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