>>> rs='AUGCUAGACGUGGAGUAG' >>> rs[12:15]='GAG' Traceback (most recent call last): File "<pyshell#119>", line 1, in ? rs[12:15]='GAG' TypeError: object doesn't support slice assignment
You can't assign to a section of a sliced string in Python 2.3 and there doesn't seem to be mention of this as a Python 2.4 feature (don't have time to actually try 2.4 yet). Q1. Does extended slicing make use of the Sequence protocol? Q2. Don't strings also support the Sequence protcol? Q3. Why then can't you make extended slicing assignment work when dealing with strings? This sort of operation (slicing/splicing of sequences represented as strings) would seem to be a very fundamental oepration when doing rna/dna/protein sequencing algorithms, and it would greatly enhance Python's appeal to those doing bioinformatics work if the slicing and extended slicing operators worked to their logical limit. Doing a cursory search doesn't seem to reveal any current PEPs dealing with extending the functionality of slicing/extended slicing operators. Syntax and feature-wise, is there a reason why Python can't kick Perl's butt as the dominant language for bioinformatics and eventually become the lingua franca of this fast-growing and funding-rich field? -- http://mail.python.org/mailman/listinfo/python-list