java.util.function

## Interface ToLongFunction<T>

- Type Parameters:
    `T` - the type of the input to the function
  Functional Interface:
    This is a functional interface and can therefore be used as the assignment target for a lambda expression or method reference.

      @FunctionalInterface
      public interface ToLongFunction<T>

  Represents a function that produces a long-valued result. This is the `long`-producing primitive specialization for `Function`.

  This is a functional interface whose functional method is `applyAsLong(Object)`.

  Since:
    1.8
  See Also:
    `Function`

- - ### Method Summary

    All Methods Instance Methods Abstract Methods
    Modifier and Type | Method and Description
    --- | ---
    `long` | `applyAsLong(T value)` Applies this function to the given argument.

- - ### Method Detail

    - #### applyAsLong

          long applyAsLong(T value)

      Applies this function to the given argument.
      Parameters:
        `value` - the function argument
      Returns:
        the function result

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