Could someone explain to me what this line of code means:
function1(num) ? 13 : 12;
I think it means
if function1(num) = 12 then function1(num) = 12
What is your input?
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Could someone explain to me what this line of code means:
function1(num) ? 13 : 12;
I think it means
if function1(num) = 12 then function1(num) = 12
What is your input?
That code is incomplete because it isn't doing anything with the value so with just that it would be equivalent to
In order to actually do something with the numbers you'd need to assign the whole thing to something for example:Code:if (function1(num)) 13;
else 12;
which is the same asCode:x = function1(num) ? 13 : 12;
Code:if (function1(num)) x = 13;
else x = 12;
You could easiy test it for yourself by picking two different values for num where one causes function1() to return true and the other has it return false.
So some values:Quote:
x = function1(num) ? 13 : 12;
if function1(num) =13
x=12
if function1(num) = 12
x = 12
if function1(num) = 5
x = 5
if function1(num) = 15
x = 15
if function1(num) = n
x = n unless n=13 then x=12
This is just ternary operator.
If num is TRUE or 1 assign 13 else assign 12
It is the simplified version of if and else.
Just the basic.
It all depends on what is in function1.
If function 1 is defined as:
thenCode:function1 = function(num) {return isFinite(num);};
would set x to 13 if num contains a finite number and to 12 if it contains infinity or something other than a number.Code:x = function1(num) ? 13 : 12;
If function 1 is defined as:
then it would set x to 12 regardless of what is in num.Code:function1 = function(num) {return false;};
You haven't showed us your function1() so what num needs to be to return true (and so set a value of 13) and what it needs to be to return false (and set a value of 12) are completely unknown to us.
If function 1 is defined as:
thenCode:function1 = function(num) {return 12===num ? true : false;};
would set x to 13 if num is 12 and set x to 12 if num is anything at all except 12.Code:x = function1(num) ? 13 : 12;
First understand that the comparison operator is == not =, otherwise you'll soon be back asking another question.
I still don't think you understand:
The statement
evaluates to 13 when function1(num) returns a non-zero value, otherwise 12.Code:function1(num) ? 13 : 12;
Or more accurately, when function1(num) returns a non-falsy value, then the above code evaluates to 13.
If function1(num) is a falsy value (false, undefined, null, NaN, 0, ""), then the above code evaluates to 12.
The question mark is a conditional operator.
condition ? expr1 : expr2
You can see that above link for further details.