[Biococoa-dev] Sequence Structure

[Koen van der Drift]

On Jul 11, 2005, at 11:57 AM, Alexander Griekspoor wrote:

> On 11-jul-2005, at 17:04, John Timmer wrote:
>
>>> [snip]
>>
>> Well, it's not just that. Untyped sequences make the sequences stupid 
>> -
>> they don't know what they are, they don't know what operations they 
>> can
>> perform, and they have to have defined responses to cope with 
>> requests for
>> operations they can't perform.

> They DO know who they are, their symbolset tells them, and they adapt 
> their behaviour based on this.

Even better, the symbolsets specifiy what type of DNA you are dealing 
with, ambiguous/unambiguous, or even a user-defined type of DNA.

>
>> Essential methods get scattered in a ton of other classes (mostly 
>> tools, but there's going to be a lot of tools in the
>> end) - you need to call through to a separate class just to figure 
>> out what
>> type of sequence you have, and something as simple as complementing 
>> anucleotide sequence requires the creation of a new object and may 
>> call
>> through about 4 different methods there (which is what I hate about 
>> BioJava,
>> as we've discussed). And yes, I hate having to test the sequence type 
>> every
>> time I think about doing anything with the sequence.

> Well, you don't have to because we do that inside the bcsequence 
> object, you can call complement on a sequence and it will do the check 
> if given the assigned symbolset it would make sense to return a value, 
> nil or throw an exception. you don't have to do anything.
>
>> If I create a nucleotide sequence, I want it to act like one.

It will, because it is made up of nucleotides, which are specified in 
the symbolset. Just naming the class BCSequenceNucleotide doesn't make 
it a nucleotide sequence. It are the individual BCSymbols that make it 
a nucleotide sequence.


- Koen.