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JavaScript JavaScript Basics (Retired) Working With Numbers The Mad Libs Challenge Revisited

Albert Lee
PLUS
Albert Lee
Courses Plus Student 1,896 Points
Posted by Albert Lee
Albert Lee
Courses Plus Student 1,896 Points

Why do we add " + " here? var questionsLeft = "[" + questions +" questions left]" works.

as title

I think we use "+" concate nothing, I don't understand why we should use "+" before the question and after the question.

1 Answer

Steven Parker
Steven Parker
231,271 Points
Steven Parker
Steven Parker
231,271 Points

The "+" is the concatenation operator, it combines strings together. The code starts with a string containing a bracket, uses the "+" to add on the number of questions, then uses another "+" to add on the rest of the message including a closing bracket.

Note that when you use this symbol with two numbers it is an addition operator instead.