Statement Termination

Disclaimer: this is a subject of near-constant debate. With the belief that some guidelines are better than no guidelines...

DO Use Semicolons

1. After a statement:

   let x;
   x = 6;
   let y = 90;
   x = x + y;
   myFunction();
   

2. When you have two statements on the same line:

   for (let i = 0 ; i < 10 ; i++) {}
   
   let x; x = 10; let y = x/2; // although for readability...don't do this
   

3. With function expressions:

   // This is an assignment statement, it needs a semicolon
   let myFunction = function(){ };
   
   // This is a multi-line assignment statement, it also needs a semicolon
   
   let myOtherFunction = function(num1,num2) {
     //...implementation code
   };
   

4. With do...while loops:

   do {
     // ... something
   } while (true);
   

Do NOT Use Semicolons

General Rule: With the exception of function expressions and do...while loops, don't follow a } with a semicolon...

1. After a block:

   if (true) { }
   
   for (;;) { }
   
   while (true) { }
   

2. Function statements (be they named or anonymous):

3. Note: these functions are not assignment expressions

   function () { }
   
   function namedFunc () { }
   

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