It wasn't my question :-) Forwarding to list...
Alan Gauld Author of the Learn To Program website http://www.alan-g.me.uk/ ----- Original Message ---- > From: Ricardo Aráoz <ricar...@gmail.com> > Subject: Re: [Tutor] Fw: list.replace -- string.swap > > > >>>> Also: How would perform string.swap(s1, s2) in the following cases: > >>>> > >> Here I mean exchanging s1 and s2 occurrences all along a string. As an > example, > >> in a text containing numerous formatted numbers, switch from english to > european > >> format: > >> 1,234,567.89 > >> 1.234.567,89 > >> meaning exchange '.' and ','. > >> > >> > >>>> * There is no secure 'temp' char, meaning that > >>>> s.replace(s1,temp).replace(s2,s1).replace(temp,s2) > >>>> will fail because any char can be part of s. > >>>> > >> The use of a temp char for marking places of one the chars to be swapped > >> is a > > >> common trick. But if the text can contain any char (even chr(0)), then > >> there > no > >> char you can safely use as temp. > >> The only workaround I know is to pass through lists. Then swap on the > >> list, > >> using eg None as temp item, and glue back the result to a string. But you > need > >> them a replace method on lists, hence my previous question ;-) > >> > >> > >>>> * Either s1 or s2 can be more than a single char. > >>>> > >> More difficult, cause you cannot simple list() the string. It must split > >> on > s1 > >> and s2, but keeping the delimiters! There is no option afaik for that in > >> string.split -- too bad! So that you must split it manually at start and > >> end > of > >> each instance of s1 and s2. Or there are other algorithms I cannot figure > out. > >> What I was asking for. > >> > > So NOW I get your question!!! > It's easy : > > >>> import string > >>> mystr = '1,234,567.89' > >>> mystr.translate(string.maketrans('.,', ',.')) > '1.234.567,89' > > Any length of string to be translated, any length of translation tables > (not only two values, any amount of them). > > HTH > > Ricardo. _______________________________________________ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
