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javascript - Why are semicolons not used after if/else statements?

I understand that it is good syntax to use semicolons after all statements in Javascript, but does any one know why if/else statements do not require them after the curly braces?

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  • Semicolon is used to end ONE statement
  • { and } begin and close a group of statements

Basically, an if-else must be followed by either a statement or a group of statements.

if-else followed by a statement:

if (condition) statement;
if (condition); // followed by a statement (an empty statement)

if-else followed by group of statements:

if (condition) {
   statement;
   statement;
}

if (condition) {
   // followed by a group of statements of zero length
}

if-else must end with a ; if it is followed by a single statement. if-else does not end with a ; when followed by a group of statements because ; is used to end a single statement, and is not used for ending a group of statements.


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