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## <a id="TokenizingFunctions">Tokenizing Functions</a> ##
### word_tokens ###


 * Syntax:

        word_tokens(string)

 * Returns an array of word tokens of `string` using non_alphanumeric characters as delimiters.
 * Arguments:
    * `string` : a `string` that will be tokenized.
 * Return Value:
    * an `array` of `string` word tokens,
    * `missing` if the argument is a `missing` value,
    * `null` if the argument is a `null` value,
    * any other non-string input value will cause a type error.

 * Example:

        word_tokens("I like the phone, awesome!");


 * The expected result is:

        [ "i", "like", "the", "phone", "awesome" ]

