Loop from 'aaaa' to 'tttt' ?

[Alexander Schmolck]

Alex Martelli <aleax at aleax.it> writes:

Just a small correction (since one of the typos is a bit confusing):
 
> def codonStrings(lenghtOfStrings, codons='acgt'):
  def codonStrings(lengthOfStrings, codons='acgt'):

>     base = len(codons)-1
>     result = lengthOfStrings * [codons[0]]
      result = lengthOfStrings * [0]
>     while 1:
>         curindex = lenghtOfStrings - 1
          curindex = lengthOfStrings - 1
>         while curindex >= 0 and result[curindex] >= base:
>             result[curindex] = 0
>             curindex -= 1
>         if curindex < 0:
>             break
>         result[curindex] += 1
>         yield ''.join( [codons[i] for i in result] )

'as