Pre-decrement or post-decrement operators are placed between two numeric strings. Javascript interview question.

In JavaScript, the statement

console.log("1" -- "1");

results in a syntax error due to the presence of two consecutive minus signs (--).

Let's break down Javascript concepts:

1. Understanding the -- Operator:

In JavaScript, -- is the decrement operator. It decreases the value of its operand by one. There are two forms:​

• Prefix Decrement (--x): Decreases the value of x by 1 and returns the new value.​
• Postfix Decrement (x--): Returns the current value of x and then decreases it by 1.​

2. Analyzing the Expression "1" -- "1":

In the given code, both operands are string literals ("1"). The expression attempts to apply the decrement operator between these two strings, which is not syntactically valid.​

3. Why This Causes a Syntax Error:

• Operator Placement: The decrement operator -- is a unary operator, meaning it operates on a single operand. It's not designed to function as a binary operator between two values. Therefore, placing -- between "1" and "1" doesn't conform to JavaScript's syntax rules.​
• Invalid Syntax: JavaScript's parser expects valid expressions. When it encounters -- between two string literals, it doesn't recognize this as a valid operation, leading to a syntax error.
  
  

Answer is :  B) SyntexError