Re: Clear entire field vs substring

[CRPence <CRPbottle@xxxxxxxxx>]

  I expect not, for a fixed-length variable.  Rather than 
initialize+assign, would that not be assign+pad; i.e. assign the target 
with the shorter value, then pad the target with blanks to the length of 
that non-varying target, which in MI is the Copy Bytes Left-Adjusted 
with Pad (CPYBLAP)?  If Shortfield in the example is 1990-bytes, I 
really doubt the 2000-byte workfield is first set entirely to blanks 
[i.e. cleared], then the first 1990-bytes overwritten [again, but this 
time] with the data from Shortfield.?  That would seem a bit daft, very 
inefficient anyhow, for a chosen implementation.

  IME a varying as target leaves 'garbage' in the target beyond the 
length of the shorter source data, from which I infer the effect was 
assign+no_pad, or set_length+assign+no_pad; noting that the 'garbage' 
perhaps is only visible using the :X debug view\formatting, and the 
'garbage' perhaps is purposely obfuscated using either :C or no 
formatting chosen as the eval\display formatting option.

Regards, Chuck

On 21 May 2012 12:19, Rory Hewitt wrote:
> Yes, doing EVAL does an initialize + assign. If the target
> (workfield, in this case) is varying, the initialize simply consists
> of setting the length to 0. If the target isn't a varying field, the
> initialize clears the target.
>
> On Mon, May 21, 2012 at 12:11 PM, Booth Martin<booth@xxxxxxxxxxxx>  wrote:
>
> > When one does:
> >    workfield = ShortField;
> >
> > doesn't that clear the entire 2000 character workfield field?
> >
> > (I understood that eval does not work like MOVE and MOVEL. Did I
> > understand wrong?)