If you are not a C, C++, or Java programmer, this chapter tells you everything you need to know about expressions and operators in JavaScript. Expressions An expression is a phrase of JavaScript that a JavaScript interpreter can evaluate to produce a value. The simplest expressions are ...
A function definition expression defines a JavaScript function, and the value of such an expression is the newly defined function. In a sense, a function definition expression is a “function literal” in the same way that an object initializer is an “object literal.” A function definition ex...
The expressionuser && user.isAdminevaluates tonull, its first operand, becauseusercontains a "falsy" value. Now, a function calledisAdministratorshould only return boolean values, as the prefixisin the name suggests. Coercion to Boolean Values# In JavaScript, a common way to coerce any value in...
The void operator evaluates an expression and returns undefined. This operator is often used to obtain the undefined primitive value, using "void(0)" (useful when evaluating an expression without using the return value).Example Useless link Click me to change the background color of body ...
Well organized and easy to understand Web building tutorials with lots of examples of how to use HTML, CSS, JavaScript, SQL, Python, PHP, Bootstrap, Java, XML and more.
&& (Logical AND) expression1 && expression2 true only if both expression1 and expression2 are true || (Logical OR) expression1 || expression2 true if either expression1 or expression2 is true ! (Logical NOT) !expression false if expression is true and vice versa Example 4: Logical Operat...
Here, && is the logical operator AND. Since both the boolean expressions x < 6 and y < 5 are true, evaluating them with the && operator also results in true.Commonly Used Logical OperatorsOperatorSyntaxDescription && (Logical AND) expression1 && expression2 true only if both expression1 and...
a[0].x // => 1: property x of expression a[0] 4.5 Invocation Expressions f(0) // f is the function expression; 0 is the argument expression. Math.max(x,y,z) // Math.max is the function; x, y and z are the arguments. ...
Thetypeofoperator returns a string representation of the type of the passed expression. There are two major points to note: Unresolvable references will produce"undefined", i.e.typeof awill return"undefined"if variableawas not declared.
Expression Add Operators Given a string that contains only digits0-9and a target value, return all possibilities to add binary operators (not unary)+,-, or*between the digits so they evaluate to the target value. Examples: "123", 6 -> ["1+2+3", "1*2*3"] ...