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[javascript/en] Re-add note about truthiness of wrapped primitives

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Previous incarnations of this section had `Number(0)` instead of
`new Number(0)`, which actually returns `0` due to the absence of the
`new` keyword; this commit re-adds that section and better still, makes
it actually correct!
This commit is contained in:
Adam Brenecki
2015-10-28 13:48:53 +10:30
parent d4d471ef50
commit c3a66e60a6
1 changed files with 4 additions and 0 deletions
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@@ -507,6 +507,10 @@ myNumber === myNumberObj; // = false
if (0){ if (0){
// This code won't execute, because 0 is falsy. // This code won't execute, because 0 is falsy.
} }
if (new Number(0)){
// This code will execute, because wrapped numbers are objects, and objects
// are always truthy.
}
// However, the wrapper objects and the regular builtins share a prototype, so // However, the wrapper objects and the regular builtins share a prototype, so
// you can actually add functionality to a string, for instance. // you can actually add functionality to a string, for instance.