partial string formatting

Question

Is it possible to do partial string formatting with the advanced string formatting methods, similar to the string template safe_substitute() function?

F

Answer 1

If you define your own Formatter which overrides the get_value method, you could use that to map undefined field names to whatever you wanted:

http://docs.python.org/library/string.html#string.Formatter.get_value

For instance, you could map bar to "{bar}" if bar isn't in the kwargs.

However, that requires using the format() method of your Formatter object, not the string's format() method.