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-.. highlight:: cpp
-
-.. _lang-string:
-
-Strings
-=======
-
-Text strings can be represented in two ways. You can
-
-1. Use the :ref:`String <lang-stringclass>` data type, which is
-part of the core as of version 0.0.9, or
-
-2. You can make a string out of an array of type :ref:`char
-<lang-char>` and null-terminate it.
-
-This page describes the second method.
-
-Examples
---------
-
-All of the following are valid declarations for strings::
-
- char str1[15];
- char str2[6] = {'m', 'a', 'p', 'l', 'e'};
- char str3[6] = {'m', 'a', 'p', 'l', 'e', '\0'};
- char str4[ ] = "maple";
- char str5[6] = "maple";
- char str6[15] = "maple";
-
-As you can see, there are several methods available for declaring and
-initializing strings:
-
-- Declare an array of ``char`` without initializing it, as with ``str1``.
-
-- Declare an array of ``char`` (with one extra ``char``) and the
- compiler will add the required null character, as with ``str2``.
-
-- Explicitly add the null character (``'\0'``), as with ``str3``.
-
-- Initialize with a string constant in quotation marks (``"..."``);
- the compiler will size the array to fit the string constant and a
- terminating null character (``str4``).
-
-- Initialize the array with an explicit size and string constant,
- (``str5``).
-
-- Initialize the array, leaving extra space for a larger string
- (``str6``).
-
-Null Termination
-----------------
-
-Generally, strings are terminated with a null character (`ASCII
-<http://en.wikipedia.org/wiki/ASCII>`_ code 0). This allows functions
-(like ``SerialUSB.print()``) to tell where the end of a string is.
-Otherwise, they would continue reading subsequent bytes of memory that
-aren't actually part of the string.
-
-This means that your string needs to have space for one more character
-than the text you want it to contain. That is why ``str2`` and
-``str5`` need to be six characters, even though "maple" is only five
--- the last position is automatically filled with a NULL
-character. ``str4`` will be automatically sized to six characters, one
-for the extra null. In the case of ``str3``, we've explicitly included
-the null character (written ``'\0'``) ourselves.
-
-Note that it's possible to have a string without a final null
-character (e.g. if you had specified the length of ``str2`` as five
-instead of six). This will break most functions that use strings, so
-you shouldn't do it intentionally. If you notice something behaving
-strangely (operating on characters not in the string), however, this
-could be the problem.
-
-Single quotes or double quotes?
--------------------------------
-
-Strings are always defined inside double quotes (``"Abc"``) and
-characters are always defined inside single quotes (``'A'``).
-
-Wrapping long strings
----------------------
-
-You can wrap long strings like this::
-
- char myString[] = "This is the first line"
- " this is the second line"
- " etcetera";
-
-Arrays of Strings
------------------
-
-It is often convenient, when working with large amounts of text,
-such as a project with an LCD display, to setup an array of
-strings. Because strings themselves are arrays, this is in actually
-an example of a two-dimensional array.
-
-In the code below, the asterisk after the datatype char ``char *``
-indicates that this is an array of "pointers". All array names are
-actually pointers, so this is required to make an array of arrays.
-Pointers are one of the more esoteric parts of C for beginners to
-understand, but it isn't necessary to understand pointers in detail to
-use them effectively here::
-
- char* myStrings[] = {"This is string 1", "This is string 2",
- "This is string 3", "This is string 4",
- "This is string 5", "This is string 6"};
-
- void setup() {
- SerialUSB.begin();
- }
-
- void loop() {
- for (int i = 0; i < 6; i++) {
- SerialUSB.println(myStrings[i]);
- delay(500);
- }
- }
-
-
-See Also
---------
-
-- :ref:`array <lang-array>`
-- :ref:`__attribute__ <arm-gcc-attribute-flash>`
-- :ref:`Variables <lang-variables>`
-
-
-.. include:: cc-attribution.txt