delete[]
Deletes any objects passed to it.
in[]
In for...in loops, assigns each successive index owned by the right object into the left variable. Everywhere else, returns a Boolean which represents whether the right object has a property by the name of the left identifier.
instanceof[]
Returns a Boolean which represents whether the first value is an instance of the right constructor.
new[]
Returns a new instance of the constructor operand.
typeof[]
Returns a string representing the argument's type. The possible strings represent only a subset of the literal types:
| Type | Result |
|---|---|
| Undefined | "undefined" |
| Null | "object" |
| Boolean | "boolean" |
| Number | "number" |
| String | "string" |
| Function | "function" |
| Anything else | "object" |
void[]
A useless legacy feature; returns undefined regardless of its operand. It is sometimes used to return false in javascript: URLs or to simply wrap a statement.