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diff --git a/source/arduino/booleanvariables.rst b/source/arduino/booleanvariables.rst
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--- a/source/arduino/booleanvariables.rst
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+.. highlight:: cpp
+
.. _arduino-booleanvariables:
-boolean
-=======
+Booleans
+========
-A **boolean** holds one of two values,
-`true <http://arduino.cc/en/Reference/Constants>`_ or
-`false <http://arduino.cc/en/Reference/Constants>`_. (Each boolean
-variable occupies one byte of memory.)
+A **boolean** holds one of two values, :ref:`true
+<arduino-constants-true>` or :ref:`false <arduino-constants-false>`.
+On a Maple, each boolean variable occupies one byte of memory, and has
+type ``bool``.
+.. warning::
+ On an Arduino, the type ``boolean`` is also provided. While the
+ Maple also has this type for compatibility, **its use is strongly
+ discouraged**. The ``bool`` type is a standard part of C++, while
+ ``boolean`` is a non-standard extension that serves no purpose.
Example
-------
::
- int LEDpin = 5; // LED on pin 5
- int switchPin = 13; // momentary switch on 13, other side connected to ground
-
- boolean running = false;
-
- void setup()
- {
- pinMode(LEDpin, OUTPUT);
+ int ledPin = 13; // LED on pin 13
+ int switchPin = 12; // momentary switch on 12, other side connected to ground
+
+ // running is a boolean variable:
+ bool running = false;
+
+ void setup() {
+ pinMode(ledPin, OUTPUT);
pinMode(switchPin, INPUT);
digitalWrite(switchPin, HIGH); // turn on pullup resistor
}
-
- void loop()
- {
- if (digitalRead(switchPin) == LOW)
- { // switch is pressed - pullup keeps pin high normally
+
+ void loop() {
+ if (digitalRead(switchPin) == LOW) {
+ // switch is pressed - pullup keeps pin high normally
delay(100); // delay to debounce switch
running = !running; // toggle running variable
- digitalWrite(LEDpin, running) // indicate via LED
+ digitalWrite(ledPin, running) // indicate via LED
}
}
-
-
-
-
-
See also
--------
-- `constants <http://arduino.cc/en/Reference/Constants>`_
-- `boolean operators <http://arduino.cc/en/Reference/Boolean>`_
-- `Variable Declaration <http://arduino.cc/en/Reference/VariableDeclaration>`_
-
-
+- :ref:`Boolean constants <arduino-constants-bool>`
+- :ref:`Boolean operators <arduino-boolean>`
+- :ref:`Variables <arduino-variables>`