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.. highlight:: cpp

.. _arduino-return:

return
======

(Keyword) Terminates a function and return a value from a function to
the calling function, if the function has non-``void`` return type.

Syntax:
-------

::

    // from within a "void" function:
    return;

    // from within a non-"void" function:
    return value;

In the second case, ``value`` should have a type which is the same as
the return type of the function, or be convertible to it (like an
``int`` to a ``long``, etc.; see :ref:`this note
<arduino-arithmetic-typeconversion>` for some references).

Examples:
---------

A function to compare a sensor input to a threshold::

     // converts analog readings between 0 and 400 to 0, and 400 up to 1.
     int checkSensor() {
        if (analogRead(0) > 400) {
            return 1;
        else {
            return 0;
        }
    }

An early ``return`` is also useful when testing a section of code
without having to "comment out" large sections of possibly buggy code,
like so::

    void loop() {

        // brilliant code idea to test here

        return;

        // the rest of a dysfunctional sketch here
        // this code will never be executed
    }

See Also
--------

- :ref:`comments <arduino-comments>`


.. include:: cc-attribution.txt