On 06/26/2016 10:51 PM, Jonas Maebe wrote:
> PS: there is an intrinsic that can help you in this process: the
> "default" intrinsic. Default(TSomeType) returns an instance of a
> particular type completely initialised to "empty" (0 for ordinal and
> floating point types, empty for strings, nil for pointers etc). You
> can assign this to e.g. your function results on entry, so that even
> when you add fields (of any type) to records you don't have to add
> additional initialisation code.
This is very helpful, thank you.
I also tried Initialize, but this does not seem to work effectively in
all cases; Default seems to work with everything I've thrown at it.
If a record type does not contain an ansistring or a dynamic array, you
also have to initialise results of functions returning such a type to
get them to return a "empty" value. If you add a field that is not a
managed type, you will also have to go through your code to add
initialisation code for that field everywhere.
So I'm not sure how this is different from any other type.
The source of my confusion -- and I suspect that of many others -- is
that I always assumed a function result was treated like a local
variable within the function, rather than a parameter to the function.
Since managed types are automatically initialized when they are local
variables, I assumed a function result was the same.
Unfortunately, the documentation does not make this sufficiently clear
in describing managed types. I guess I should file a documentation bug.
Thanks,
David
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