On Tue, 19 Apr 2011 10:34:27 +1000, James Mills wrote: > Normally it's considered bad practise to concatenate strings.
*Repeatedly*. There's nothing wrong with concatenating (say) two or three strings. What's a bad idea is something like: s = '' while condition: s += "append stuff to end" Even worse: s = '' while condition: s = "insert stuff at beginning" + s because that defeats the runtime optimization (CPython only!) that *sometimes* can alleviate the badness of repeated string concatenation. See Joel on Software for more: http://www.joelonsoftware.com/articles/fog0000000319.html But a single concatenation is more or less equally efficient as string formatting operations (and probably more efficient, because you don't have the overheard of parsing the format mini-language). For repeated concatenation, the usual idiom is to collect all the substrings in a list, then join them all at once at the end: pieces = [] while condition: pieces.append('append stuff at end') s = ''.join(pieces) -- Steven -- http://mail.python.org/mailman/listinfo/python-list