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<a name="Statements"></a>
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Next: <a href="Constants.html#Constants" accesskey="n" rel="next">Constants</a>, Previous: <a href="Symbol-Intro.html#Symbol-Intro" accesskey="p" rel="previous">Symbol Intro</a>, Up: <a href="Syntax.html#Syntax" accesskey="u" rel="up">Syntax</a> &nbsp; [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="AS-Index.html#AS-Index" title="Index" rel="index">Index</a>]</p>
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<hr>
<a name="Statements-1"></a>
<h3 class="section">3.5 Statements</h3>

<a name="index-statements_002c-structure-of"></a>
<a name="index-line-separator-character"></a>
<a name="index-statement-separator-character"></a>

<p>A <em>statement</em> ends at a newline character (&lsquo;<samp>\n</samp>&rsquo;) or a
<em>line separator character</em>.  The line separator character is target
specific and described in the <em>Syntax</em> section of each
target&rsquo;s documentation.  Not all targets support a line separator character.
The newline or line separator character is considered to be part of the
preceding statement.  Newlines and separators within character constants are an
exception: they do not end statements.
</p>
<a name="index-newline_002c-required-at-file-end"></a>
<a name="index-EOF_002c-newline-must-precede"></a>
<p>It is an error to end any statement with end-of-file:  the last
character of any input file should be a newline.
</p>
<p>An empty statement is allowed, and may include whitespace.  It is ignored.
</p>
<a name="index-instructions-and-directives"></a>
<a name="index-directives-and-instructions"></a>
<p>A statement begins with zero or more labels, optionally followed by a
key symbol which determines what kind of statement it is.  The key
symbol determines the syntax of the rest of the statement.  If the
symbol begins with a dot &lsquo;<samp>.</samp>&rsquo; then the statement is an assembler
directive: typically valid for any computer.  If the symbol begins with
a letter the statement is an assembly language <em>instruction</em>: it
assembles into a machine language instruction.
Different versions of <code>as</code> for different computers
recognize different instructions.  In fact, the same symbol may
represent a different instruction in a different computer&rsquo;s assembly
language.
</p>
<a name="index-_003a-_0028label_0029"></a>
<a name="index-label-_0028_003a_0029"></a>
<p>A label is a symbol immediately followed by a colon (<code>:</code>).
Whitespace before a label or after a colon is permitted, but you may not
have whitespace between a label&rsquo;s symbol and its colon. See <a href="Labels.html#Labels">Labels</a>.
</p>
<p>For HPPA targets, labels need not be immediately followed by a colon, but
the definition of a label must begin in column zero.  This also implies that
only one label may be defined on each line.
</p>
<div class="smallexample">
<pre class="smallexample">label:     .directive    followed by something
another_label:           # This is an empty statement.
           instruction   operand_1, operand_2, &hellip;
</pre></div>

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