santiago.basu...@gmail.com wrote: > Hello everybody. I'm writing a CLI program to do some search. It's an > internal tool. I'd like to provide the option to my user to format the > results as he/she'd like. Something similar to strftime on the datetime > module. > > Example: > > from datetime import datetime > d = datetime.utcnow() > d.strftime("%Y-%m-%d") # '2015-04-18' > d.strftime("%y-%m-%d") # '15-04-18' > d.strftime("Today it's the %dth day in the %mth month of %Y") # 'Today > it's the 18th day in the 04th month of 2015' # Don't pay attention to > ordinals, just simple example. > > Now, an example of with my application. Suppose my app search cars: > > python search_cars.py -F "Brand %B, model %m, year %Y" # Brand Ford, > model Focus, year 1996 > python search_cars.py -F "%B - %m (%y)" # Ford - Focus (96) > > I'd provide my user with a table like: > > %B = Brand > %m = Model > %Y = Year format YYYY > %y = Year format YY > %s = Seller name > ... etc... > > Thanks a lot for your help!
Make a dict to map the format to a function that extracts the value you are interested in from a record you found with your search. Then replace the format in the template with the value returned from that function. >>> import re >>> record = dict(brand="Ford", model="Focus", year=1996) >>> format = {"B": lambda r: r["brand"], ... "m": lambda r: r["model"], ... "Y": lambda r: str(r["year"]), ... "y": lambda r: "{:02}".format(r["year"] % 100), ... } >>> template = "Brand %B, model %m, year %Y" >>> re.compile("%(.)").sub(lambda m: format[m.group(1)](record), template) 'Brand Ford, model Focus, year 1996' >>> template = "%B - %m (%y)" >>> re.compile("%(.)").sub(lambda m: format[m.group(1)](record), template) 'Ford - Focus (96)' To allow literal % signs add format = { ... "%": lambda r: "%" } to the lookup dict. For alternative approaches have a look at string.Template, str.format() etc. -- https://mail.python.org/mailman/listinfo/python-list