Re: Smuggling information to enums
Roedy Green wrote:
On 24 Mar 2009 15:33:02 GMT, Andreas Leitgeb
<email@example.com> wrote, quoted or indirectly quoted
someone who said :
Does it at least seem as if I had understood your question?
Yes, you understood. I was hoping I had overlooked something.
In my case I was rewriting my CSVReader to use enums. A CSVReader can
be configured with the various characters you want to use for
separator, quote and comment. The enum needs to know these facts.
Further there could be two different CSVReader objects in RAM at once.
That means I would want two versions of the enum, each with a
different set of instance data.
I think the way it will have to work is pass in the magic constants on
every call as parameters so that only one uncustomised copy of the
enum is needed.
The parms on the enum constant constructors pretty well have to be
constants, or something public and static since almost nothing is
known in the context of those parms.
Are you sure you should be using enum to do as much as you are trying to
make it do?
Remember options such as an EnumMap mapping from the enum to objects
that do the actual work, and are aware of separators etc. Each CVSReader
would have its own instance of the EnumMap.
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