The shape is just the tip of the iceberg. If the verb in question were
m}, there would be no way to restore (a).
And in general, many in-place verbs may have executed before the error.
The original (a) may be long gone.
If you foresee this as a problem, you should execute 9!:53(0) to turn
off early assignment.
Henry Rich
On 10/3/2016 10:34 PM, Raul Miller wrote:
There are two reasons to be concerned about the value of a in the error case.
The minor one is error recovery. This is a simple example, and easy to
understand. What happens, though, when someone uses try./catch. with a
large code base? This issue would not be easy to isolate, nor will it
be easy to understand.
A bigger issue is the one you mentioned here: debugging. When
debugging code which takes a long time to run, you will at times want
to fix the issue and continue, rather than burning the time necessary
to restart from the beginning.
And, also, this seems like it will be hard to explain and at the same
time distract from issues which are more important.
But keep in mind that I am not recommending the (a=:0)](a) mechanism
for this example. I made that suggestion for hypothetical cases.
I am instead recommending that the shape of a be saved somewhere and
that a have its shape set to what it originally was, in the error
case.
Is there some reason why you think that restoring a's shape in the
error case is not a viable approach here?
Thanks,
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