[M3devel] Rd.GetText Question

[Tony Hosking]

Hmm.  GetText(rd, Rd.Length(rd)) will fail with a run-time error if Length returns -1 because -1 is not a CARDINAL.  I don't think this is generally a safe idiom.

On Jul 8, 2011, at 10:44 PM, Ken Durocher wrote:

> The Rd interface defines GetText as GetText(rd: T; len: CARDINAL): TEXT;
> 
> I've noticed in different values for len in different places.  Some use Rd.Length(rd) while others use LAST(CARDINAL).
> 
> The latter would limit the text to about 2GB on a 32bit system, correct? But does Rd.Length() always know what the length will be?
> 
> The interface for Rd states this for Rd.Length():
>  "If len(rd) is unknown to the implementation of an intermittent reader, Length(rd) returns -1."
> 
> So my question is, which should I use? Another option would be reading in some arbitrary amount and then looping until EOF. Which method is best?
> 
> Thanks.