I'm trying to format a string using key-value pairs where the variable modifier in the string is referenced by the name of the key.
How would I go about this? Here is my code:
given_string2 = "I'm %(name)s. My real name is %(nickname)s, but my friends call me %(name)s."
def sub_m(name, nickname):
return given_string2 %{name:nickname}
print sub_m("Mike","Goose")
Your problem is here: given_string2 % {name: nickname}
This works:
>>> "I'm %(name)s. My real name is %(nickname)s, but my friends call me %(name)s." % {'name': "Mike", 'nickname': "Goose"}
"I'm Mike. My real name is Goose, but my friends call me Mike."
def sub_m(name, nickname)
print "I'm %s. My real name is %s, but my friends call me %s" % (name, nickname, name)
I don't think you're creating the dictionary the way you think you are. the %(name) and %(nickname) placeholders must refer to a valid key in the dictionary you pass. Thus, you need something like:
'the quick brown %(animal)s jumped over the %(adjective)s dog' % {"animal": "fox", "adjective": "lazy"}
What you have is a dictionary with a key "Mike" and a value of "Goose". If you changed %(name)s and %(nickname)s in your original string to %(Mike)s, you'd get Goose substituted 3 times.
You can simply use positional parameters, like this:
given_string2 = "I'm {0}. My real name is {1}, but my friends call me {0}."
def sub_m(name, nickname):
return given_string2.format(name, nickname)
print sub_m("Mike","Goose")
The {} formatters refer to the 0-indexed positional arguments of the format() method applied to the string.