Is it bad practice to use + instead of %s

Hi Ethan,

Concatenation (your first example) and Interpolation (second example) are two different ways of constructing a string with variables. Sometimes only one will work... other times both will work but one is usually better.

In your example, it doesn't make that much of a difference, although Interpolation would still be better.
But what if you were to have 3 or 4 or 7 variables to add? Do you really want to type "string " + variable + " string " + variable ... or would you rather "%s, <string goes here> %s %s!", variable1, variable2, variable 3.
Or what if there is a more complex formatting needed inside of the string... your concatenated string could span many, many + signs and "".
Finally, there is the subject of readability. Even with your example, the concatenated string is much more difficult to read in code than the interpolated one. With the concatenated one (even with better spacing), takes an extra minute to see what it's purpose or output will be.

So, while sometimes concatenation is fine, it usually is not the best way. In fact, I don't really see it used that often. In my opinion, yes, concatenation is "bad practice" and one should use interpolation unless absolutely necessary otherwise.

Keep Coding! :)