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<a name="M2-Scope"></a>
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<a name="The-Scope-Operators-_003a_003a-and-_002e"></a>
<h4 class="subsubsection">15.4.9.8 The Scope Operators <code>::</code> and <code>.</code></h4>
<a name="index-scope"></a>
<a name="index-_002e_002c-Modula_002d2-scope-operator"></a>
<a name="index-colon_002c-doubled-as-scope-operator"></a>
<a name="index-_003a_003a_002c-in-Modula_002d2"></a>

<p>There are a few subtle differences between the Modula-2 scope operator
(<code>.</code>) and the <small>GDB</small> scope operator (<code>::</code>).  The two have
similar syntax:
</p>
<div class="smallexample">
<pre class="smallexample">
<var>module</var> . <var>id</var>
<var>scope</var> :: <var>id</var>
</pre></div>

<p>where <var>scope</var> is the name of a module or a procedure,
<var>module</var> the name of a module, and <var>id</var> is any declared
identifier within your program, except another module.
</p>
<p>Using the <code>::</code> operator makes <small>GDB</small> search the scope
specified by <var>scope</var> for the identifier <var>id</var>.  If it is not
found in the specified scope, then <small>GDB</small> searches all scopes
enclosing the one specified by <var>scope</var>.
</p>
<p>Using the <code>.</code> operator makes <small>GDB</small> search the current scope for
the identifier specified by <var>id</var> that was imported from the
definition module specified by <var>module</var>.  With this operator, it is
an error if the identifier <var>id</var> was not imported from definition
module <var>module</var>, or if <var>id</var> is not an identifier in
<var>module</var>.
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