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<a name="M2-Checks"></a>
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Next: <a href="M2-Scope.html#M2-Scope" accesskey="n" rel="next">M2 Scope</a>, Previous: <a href="Deviations.html#Deviations" accesskey="p" rel="previous">Deviations</a>, Up: <a href="Modula_002d2.html#Modula_002d2" accesskey="u" rel="up">Modula-2</a> &nbsp; [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Concept-Index.html#Concept-Index" title="Index" rel="index">Index</a>]</p>
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<a name="Modula_002d2-Type-and-Range-Checks"></a>
<h4 class="subsubsection">15.4.9.7 Modula-2 Type and Range Checks</h4>
<a name="index-Modula_002d2-checks"></a>

<blockquote>
<p><em>Warning:</em> in this release, <small>GDB</small> does not yet perform type or
range checking.
</p></blockquote>

<p><small>GDB</small> considers two Modula-2 variables type equivalent if:
</p>
<ul>
<li> They are of types that have been declared equivalent via a <code>TYPE
<var>t1</var> = <var>t2</var></code> statement

</li><li> They have been declared on the same line.  (Note:  This is true of the
<small>GNU</small> Modula-2 compiler, but it may not be true of other compilers.)
</li></ul>

<p>As long as type checking is enabled, any attempt to combine variables
whose types are not equivalent is an error.
</p>
<p>Range checking is done on all mathematical operations, assignment, array
index bounds, and all built-in functions and procedures.
</p>


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