JavaScript: The Good Parts

Block-less Statements

An if or while or do or for statement can take a block or a single statement. The single statement form is another attractive nuisance. It offers the advantage of saving two characters, a dubious advantage. It obscures the program's structure so that subsequent manipulators of the code can easily insert bugs. For example:

if (ok)
    t = true;

can become:

if (ok)
    t = true;
    advance(  );

which looks like:

if (ok) {
    t = true;
    advance(  );
}

but which actually means:

if (ok) {
    t = true;
}
advance(  );

Programs that appear to do one thing but actually do another are much harder to get right. A disciplined and consistent use of blocks makes it easier to get it right.