I was recently writing some documentation for the Array.forEach() method (part of ES5, but most browsers other than IE support it now) and worrying about the fact that there is no clean way to terminate the iteration prematurely. Nothing like the break statement, that is. If you really want to get out of the loop, the function you pass to forEach() has to throw something. And the forEach() method won't catch it for you, so you've got to write your own try block.
Then, when working with the new array predicate method Array.some(), I realized that we don't have to think of it as a predicate method. If we ignore the return value, it is an iterator method that works just like Array.forEach() except that if your function returns true (or any truthy value) then the loop terminates. So inside of the function you pass, a plain return statement with no value is like using a continue statement. And "return true" is like a break statement, causing the loop to terminate. The implicit return that occurs at the end of the function body returns undefined, which is like returning false--it keeps the loop going.
The Array.every() method is not so useful this way: you have to explicitly return a truthy value to keep the loop going, so an implicit return at the end of the function body would act like a break statement.
The problem I see with using some() in this way is a stylistic one: the name really doesn't look like the name of an iterator the way that "each" and "every" do.
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