At what point does JavaScript determine the left-hand side of an assignment — is it before or after the right-hand side is evaluated?  For example, what does this code do?  var arr = [{thing:1},{thing:2},{thing:3},{last:true}]; arr[arr.length - 1]...

If only the second operand in addition is a string then the output is a string:  let a = 1 + '2'; console.log(typeof a);  // string   And if, instead, only the first operand is a string, then the output is still a string:  let b = '1'...

In Javascript certain operators are processed before others:  1 + 2 * 3 // 1 + (2 * 3) // 7 because * has higher precedence than +  1 === 0 + 1 // 1 === (0 + 1) // true because + has a higher precedence than ===   The MDN has a full breakdown of all...

a = 1; b = "1"; if (a == b && a = 1) {     console.log("a==b"); }   The Javascript code above will result in an error in the if statement in Google Chrome 26.0.1410.43:      Uncaught ReferenceError: Invalid left-hand side in a...

I understand that the assignment operator is right associative.  So for example  x = y = z = 2 is equivalent to (x = (y = (z = 2)))  That being the case, I tried the following:  foo.x = foo = {a:1}   I expected that the object foo would be created wi...

In all of the JavaScript operator precedence charts I can find (like this one and this one), the logical AND (&&) has slightly higher precedence to the logical OR (||).  I can't seem to figure out an expression where the result is differe...

In JavaScript, how is the following statement to be interpreted:  cond1 && !await f()   This is an excerpt from the line  if(cond1 && !await f()){     do_stuff(); }   inside a production application. chrome seems to be fine with it, b...

I'm trying to create a simple javascript program that reads keydown events and translates them into movement on an HTML canvas. I've had a fairly large degree of success so far, I'm having a strange issue with (what I assume is) arrow key...

In the Code Academy JS course, Dragon Slayer 2/6, the following text is used in the hint to describe the order of operations for the code I included in the title.     How does this code work?      Math.floor(Math.random() * 5 + 1);         First we u...

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