[fpc-devel] An extension of fpc language: the BASED construct

[Giuliano Colla]

Il 27/12/2017 15:05, Sven Barth via fpc-devel ha scritto:

> No matter the syntax that might be chosen for this it will likely be 
> sufficient to handle that feature by an absolutevarsym with a boolean 
> flag or something like that. The difference to an ordinary absolute 
> variable appears to be too small to warrant a new sym type.
>

After struggling sometime to find out the best way to implement the 
based feature without adding a new keyword, I found that the syntax:

aVar: anyType ABSOLUTE somePTR^;

can be implemented with minimal changes.

Attached the patch which does the trick, and which works like the old 
proven one.

It doesn't support *implicit* dereferencing, because I've left untouched 
the code which filters it out.
One could remove the filtering for consistency, but I don't like very 
much the idea: the aim of such a feature is to provide a more readable 
and understandable code, not the opposite.

Giuliano

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