Say I do the following:
>>> a = [email protected]
>>> uname, domain = a.split('@')
But what if I only ever want domain, and never uname? For example, if I only ever wanted uname and not domain, I could do this:
>>> uname, = a.split('@')
Is there a better way to split a into a tuple and have it throw away uname?
To take into account some of the other answers, you have the following options:
If you know that the string will have an '@' symbol in it then you can simply do the following:
>>> domain = a.split('@')[1]
If there is a chance that you don't have an '@' symbol, then one of the following is suggested:
>>> domain = a.partition('@')[2]
Or
try:
domain = a.split('@')[1]
except IndexError:
print "Oops! No @ symbols exist!"
You could use your own coding style and specify something like "use '_' as don't care for variables whose value you want to ignore". This is a general practice in other languages like Erlang.
Then, you could just do:
uname, _ = a.split('@')
And according to the rules you set out, the value in the _ variable is to be ignored. As long as you consistently apply the rule, you should be OK.
_ is actually quite well established, see What is the purpose of the single underscore “_” variable in Python?.If you know there's always an @ in your string, domain = a.split('@')[1] is the way to go. Otherwise check for it first or add a try..except IndexError block aroudn it.
domain = a.partition('@')[2]. This will set domain to '' if there is no @ in the string, and will also only split on the first @ if there is more than one.This gives you an empty string if there's no @:
>>> domain = a.partition('@')[2]
If you want to get the original string back when there's no @, use this:
>>> domain = a.rpartition('@')[2]
This could work:
domain = a[a.index("@") + 1:]
