I have a function generate_username that generates a username (obviously).
The values fname and lname are mandatory, so no issues there. However, mname is NOT a mandatory field so, it may be blank, which breaks this code.
Any suggestions on how to ask ruby to only print the mname value if it exists or is set and ignore it if the user left it blank?
def generate_username
self.username = fname.to_s.split("")[0] + mname.to_s.split("")[0] + lname.to_s
end
You could try this (parentheses are important):
def generate_username
self.username = fname.to_s.split("")[0] << (mname.to_s.split("")[0] || "") << lname.to_s
end
can't convert nil into StringThrowing a simple ternary operator in to check if the value is blank? should do the trick.
def generate_username
self.username = fname.to_s.split("")[0] + (mname.blank? ? "" : mname.to_s.split("")[0]) + lname.to_s
end
In ruby 1.9
def generate_username
"#{fname[0]}#{mname.to_s[0]}#{lname}"
end
or
def generate_username
fname[0]+mname.to_s[0].to_s+lname
end
In ruby 1.8, replace all the [0] with [0, 1] (This point added after being pointed out by Peter).
mname.to_s ensures you get a string; when mname is nil it will be an empty string "".String#[0] picks up the first character of that string; when the string is empty, it will return nil.#{ } within " " expands the ruby code, and turns it into a string; particularly turns nil into an empty string "".
fname[0] gives me a Fixnum instead of the first character (while 1.9.2 gives me the first character ;D)
[0,1] will work.fname[0] over fname.split("")[0] :D