Extending string formatting with custom conversion types

问题

string.Formatter allows the extension of new style formatting with custom conversion types.

Is this possible for the older "%"-style formatting strings too? Is there a library for this?

回答1:

Maybe

class CustomFormat(object):
    def __init__(self, obj):
        self.Object = obj

    def __str__(self):
        return str(self.Object).upper()  # your magic goes here...

print "abc%s" % customFormat("hello")
# abcHELLO

来源：https://stackoverflow.com/questions/18394385/extending-string-formatting-with-custom-conversion-types