Merge pull request getify#388 from kemar/typo_double_the

Typo: double "the"

Author: getify

types & grammar/ch4.md

@@ -642,7 +642,7 @@ I find this to be cleaner code than the previous `>= 0` / `== -1` clutter.
 
 There's one more place `~` may show up in code you run accross: some developers use the double tilde `~~` to truncate the decimal part of a `number` (i.e., "coerce" it to a whole number "integer"). It's commonly (though mistakingly) said this is the same result as calling `Math.floor(..)`.
 
-How `~~` works is that the first `~` applies the `ToInt32` "coercion" and does the the bitwise flip, and then the second `~` does another bitwise flip, flipping all the bits back to the original state. The end result is just the `ToInt32` "coercion" (aka truncation).
+How `~~` works is that the first `~` applies the `ToInt32` "coercion" and does the bitwise flip, and then the second `~` does another bitwise flip, flipping all the bits back to the original state. The end result is just the `ToInt32` "coercion" (aka truncation).
 
 **Note:** The bitwise double-flip of `~~` is very similar to the parity double-negate `!!` behavior, explained in the "Explicitly: * --> Boolean" section later.