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-.. highlight:: cpp
-
-.. _lang-static:
-
-``static``
-==========
-
-The ``static`` keyword can be used to create variables that are
-visible to only one function. However, unlike local variables that get
-created and destroyed every time a function is called, ``static``
-variables persist beyond the function call, preserving their data
-between function calls.
-
-Variables declared as ``static`` will only be created and initialized
-the first time a function is called.
-
-.. note:: This is only one use of the ``static`` keyword in C++. It
- has some other important uses that are not documented here; consult
- a reliable C++ reference for details.
-
-Example
--------
-
-One use case for ``static`` variables is implementing counters that
-last longer than the functions which need them, but shouldn't be
-shared to other functions. Here's an example::
-
- void setup() {
- SerialUSB.begin();
- }
-
- void loop() {
- int reading;
- if (timeToReadSensors()) {
- reading = readSensors();
- }
- // do something with reading
- }
-
- int readSensors() {
- static int numSensorReadings = 0;
- numSensorReadings++;
- if (numSensorReadings % 100 == 0) {
- SerialUSB.print("just got to another 100 sensor readings");
- }
- return analogRead(...);
- }
-
-In this example, the static variable ``numSensorReadings`` is
-initialized to zero the first time ``readSensors()`` is called, and
-then incremented, so it starts out at one. Subsequent calls to
-``readSensors()`` won't reset ``numSensorReadings`` to zero, because
-it was declared ``static``. Thus, ``numSensorReadings`` is a count of
-the number of times that ``readSensors()`` has been called.
-
-.. include:: /arduino-cc-attribution.txt