Re: Top 10 IDL Requests

[davidf(at)dfanning.com (David Fanning)]

Doug Reynolds (dsreyn@ll.mit.edu) writes:

> I meant the latter - resizing a common block without exiting IDL.  During
> program development, I often find that I want to add a variable to a common
> block.  Of course, when I attempt to recompile, IDL says something like this:
> 
>    % Attempt to extend common block: TEST
> 
> It's not particularly difficult to exit and restart IDL, but any variables
> I had defined then need to be reset.  Unfortunately, .reset_session has the
> same problem, because in addition to common blocks, it appears to kill any
> variables defined at the main level.
> 
> I don't know how common blocks are implemented internally (an array of
> pointers, perhaps?), but it seems that if IDL can dynamically redimension
> arrays, it also ought to be able to dynamically resize common blocks also.

It is just that resizing COMMON blocks during the IDL session
is such a BAD idea (spend just two seconds thinking of what
havoc might ensue) that RSI (to their great credit) refuses to
do it, even if they could. Bravo, I say.

Cheers,

David

-- 
David Fanning, Ph.D.
Fanning Software Consulting
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