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diff --git a/source/arduino/sizeof.rst b/source/arduino/sizeof.rst deleted file mode 100644 index 7c31809..0000000 --- a/source/arduino/sizeof.rst +++ /dev/null @@ -1,64 +0,0 @@ -.. highlight:: cpp - -.. _arduino-sizeof: - -sizeof() -======== - -The ``sizeof`` operator on the Maple returns the number of bytes -needed to store a value of a given type\ [#fcharsize]_. This can be -an ordinary numeric type, like ``int``. It can be something more -complicated, like a ``struct`` or ``union``. If the argument to -``sizeof`` is an array, it returns the total number of bytes occupied -by the array. - -The general syntax looks like this:: - - sizeof(type) - sizeof(var) - -Example -------- - -The ``sizeof`` operator is useful for dealing with arrays (such as -strings) where it is convenient to be able to change the size of the -array without breaking other parts of the program. - -This program prints out a text string one character at a time. Try -changing the text phrase:: - - char myStr[] = "this is a test"; - int i; - - void setup() { - Serial.begin(9600); - } - - void loop() { - for (i = 0; i < sizeof(myStr) - 1; i++) { - Serial.print(i, DEC); - Serial.print(" = "); - Serial.println(myStr[i], BYTE); - } - } - - -Note that ``sizeof`` returns the total number of bytes. So for larger -variable types such as ``int``, the :ref:`for loop <arduino-for>` -would look something like this:: - - for (i = 0; i < (sizeof(myInts)/sizeof(int)) - 1; i++) { - // do something with myInts[i] - } - -.. rubric:: Footnotes - -.. [#fcharsize] Technically (and pedantically) speaking, ``sizeof`` - returns a multiple of the number of bits a ``char`` occupies in - memory. However, on the Maple (this goes for most C++ - implementations), a ``char`` occupies 8 bits = 1 byte. All the C++ - standard guarantees, however, is that a ``char`` occupies at - *least* 8 bits. - -.. include:: cc-attribution.txt - |