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<h3 class="section">3.5 Statements</h3>
<p><a name="index-statements_002c-structure-of-130"></a><a name="index-line-separator-character-131"></a><a name="index-statement-separator-character-132"></a>
A <dfn>statement</dfn> ends at a newline character (‘<samp><span class="samp">\n</span></samp>’) or a
<dfn>line separator character</dfn>. The line separator character is target
specific and described in the <em>Syntax</em> section of each
target'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-133"></a><a name="index-EOF_002c-newline-must-precede-134"></a>It is an error to end any statement with end-of-file: the last
character of any input file should be a newline.
<p>An empty statement is allowed, and may include whitespace. It is ignored.
<p><a name="index-instructions-and-directives-135"></a><a name="index-directives-and-instructions-136"></a><!-- "key symbol" is not used elsewhere in the document; seems pedantic to -->
<!-- @defn{} it in that case, as was done previously... doc@cygnus.com, -->
<!-- 13feb91. -->
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 ‘<samp><span class="samp">.</span></samp>’ 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 <dfn>instruction</dfn>: it
assembles into a machine language instruction.
Different versions of <samp><span class="command">as</span></samp> for different computers
recognize different instructions. In fact, the same symbol may
represent a different instruction in a different computer's assembly
language.
<p><a name="index-g_t_0040code_007b_003a_007d-_0028label_0029-137"></a><a name="index-label-_0028_0040code_007b_003a_007d_0029-138"></a>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's symbol and its colon. See <a href="Labels.html#Labels">Labels</a>.
<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.
<pre class="smallexample"> label: .directive followed by something
another_label: # This is an empty statement.
instruction operand_1, operand_2, ...
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