Using two different structs for the same data

[iso9001]

I'm not sure how to go about this, but I have a struct problem and without assigning pointers to constants I'm not sure what the best way to do this is.

I have two potential data streams coming in. Farm animals in my example

1. Pig, Goat, Monkey, Dog, Cow, Horse
2. Monkey, Pig, Dog, Horse, Goat, Cow

(Aside, I don't know much about farm animals so I ran out and added a monkey in. I tried to sort #1 by size, but hell if I know whats larger between a dog and a monkey, and likewise sorting #2 by intelligence, I'm not sure what goat really ranks, you can teach a horse to do more things so I put that over goat...... geez its late)

At compile time I don't know which data steam I'm going to get and I'd rather not write my functions all twice for either data set. So it would be ideal to use structs for this, but I'm not sure how I can dynamically define a struct like that.

I want to use data.PIG but can't figure out how to make that mean data.[0] and data[1] depending on stream identification,

Ideas ?

[Ttelmah]

Define both structures.
Create a union between the two.

Best Wishes

[SimpleAsPossible]

Am I understanding this correctly? You are receiving a data stream, and its elements can be in one of two known orders. Then you want to be able to conveniently access the data the way the stream should be interpreted.

So, with a small (ha!) paragraph of disclaimers, here's some code that may help explain.

I assume you have a way to detect which stream type you have received and set the Type variable within the data stream struct. I'm also assuming that the elements are all ints, though they can be other types or structures as needed. I always name all my unions and struct types (usually with prefixes for disambiguation purposes, but not here), probably for the same reason I use parentheses in any expression that gets more complicated than + and -. I also always make Unknown the first element of an enum, as a reminder to initialize it to a reasonable default. I didn't compile this code, it's for illustration only. And yes, it's brute force. It's really more like I'd code on a larger processor, not a PIC. Lots more Get/Set functions are needed.

[Neutone]