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<p class='vspace'></p><h2>{} Curly Braces</h2>
<p>Curly braces (also referred to as just "braces" or as "curly brackets") are a major part of the C programming language. They are used in several different constructs, outlined below, and this can sometimes be confusing for beginners.
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<p class='vspace'></p><p>An opening curly brace "{" must always be followed by a closing curly brace "}". This is a condition that is often referred to as the braces being balanced. The Arduino IDE (integrated development environment) includes a convenient feature to check the balance of curly braces. Just select a brace, or even click the insertion point immediately following a brace, and its logical companion will be highlighted.
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<p class='vspace'></p><p>At present this feature is slightly buggy as the IDE will often find (incorrectly) a brace in text that has been "commented out."
</p>
<p class='vspace'></p><p>Beginning programmers, and programmers coming to C from the BASIC language often find using braces confusing or daunting. After all, the same curly braces replace the RETURN statement in a subroutine (function), the ENDIF statement in a conditional and the NEXT statement in a FOR loop.
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<p class='vspace'></p><p>Because the use of the curly brace is so varied, it is good programming practice to type the closing brace immediately after typing the opening brace when inserting a construct which requires curly braces. Then insert some carriage returns between your braces and begin inserting statements. Your braces, and your attitude, will never become unbalanced.
</p>
<p class='vspace'></p><p>Unbalanced braces can often lead to cryptic, impenetrable compiler errors that can sometimes be hard to track down in a large program. Because of their varied usages, braces are also incredibly important to the syntax of a program and moving a brace one or two lines will often dramatically affect the meaning of a program.
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<p class='vspace'></p><h4><strong>The main uses of curly braces</strong></h4>
<h4>Functions</h4>
<pre> void myfunction(datatype argument){
statements(s)
}
</pre>
<p class='vspace'></p><h4>Loops</h4>
<pre> while (boolean expression)
{
statement(s)
}
do
{
statement(s)
} while (boolean expression);
for (initialisation; termination condition; incrementing expr)
{
statement(s)
}
</pre>
<p class='vspace'></p><h4>Conditional statements</h4>
<p class='vspace'></p><pre> if (boolean expression)
{
statement(s)
}
else if (boolean expression)
{
statement(s)
}
else
{
statement(s)
}
</pre>
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<p class='vspace'></p><p><em>Corrections, suggestions, and new documentation should be posted to the <a class='urllink' href='http://arduino.cc/forum/index.php/board,23.0.html' rel='nofollow'>Forum</a>.</em>
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