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

Nikanoras Zavadskij
Nikanoras Zavadskij
1,938 Points
Posted by Nikanoras Zavadskij
Nikanoras Zavadskij
1,938 Points

I don't understand how this var questionsLeft = "[" + questions +" questions left]" works.

The part that i don't understand is " + questions +" . Why do you use ""? isn't it suppose print about just a word? And those plus signs before and after. I understand why you need + after, but i don't understand why before.

3 Answers

Steven Parker
Steven Parker
231,007 Points
Steven Parker
Steven Parker
231,007 Points

When used with strings, the + is a "concatenation operator". This means it joins strings together. The quote marks surround literal strings which will be used just as they are. So the whole thing builds a long string that starts with a bracket, then the number stored in "questions", then the phrase " questions left]".

So for example, if the variable "questions" was holding the number 3, after this statement runs the variable "questionsLeft" would contain this string :point_right: [3 questions left]

Victor Okere
Victor Okere
872 Points

i dont still understand that part its suppose to be questionleft=question +"questionleft" because we already gave the variable name a value of 3.

Steven Parker
Steven Parker
231,007 Points
Steven Parker
Steven Parker
231,007 Points

And since the variable was given the value of 3, then this statement will convert it to a string and combine it the other words and symbols to display "[3 questions left]" on the screen.

James Dennan
James Dennan
2,441 Points
James Dennan
James Dennan
2,441 Points

Is this just a particularly hard bit of Javascript to get your head around or is it just very badly explained? I've watched this video about 6 times now and am none the wiser. AAARRGhhhh!!!!!

Immanuel Jaeggi
Immanuel Jaeggi
5,164 Points
Immanuel Jaeggi
Immanuel Jaeggi
5,164 Points

The way I understand it....in {}.

var questions = 3;
{var is the named location; questions is the value}

var questionsLeft = " [" + questions + " questions left]";
{We need a new value (questionsLeft) for a placeholder to contain the information we want to see in the dialog box; " [" + questions + " questions left]"; second pair of quotes followed by a space gives us an actual space in the dialog box we see at the end; + of course is the string; questions is our number 3; third pair of quotes followed by a space, again actual space we see in the result; questions left are the actual words in the dialog box}

var adjective = prompt('Please type an adjective' + questionsLeft); {Our first prompt}

questions -= 1; {subtracts one question :) }

sorry if it was a bit long-winded, hopes it helped someone ;) Cheers