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<html>
<head>
<title>C++ Local Variables.</title>
</head>
<body bgcolor="#dddddd">
<font color=brown>
<hr>
<center><h1>C++ Local Variables.</h1></center>
<hr>
<p>
There is not much difference between
<a href=../../C/SYNTAX/glo_int_vars.html> C local variables</a> but there
is one important feature that should be noted.
<ul>
<li>Variable definitions are now considered to be executable statements.
</ul>
This means that you can now put variable definitions anywhere in the code
and not jut at the start of a
<a href=../../C/glossary.html#block>block.</a>
Here is an example.
<p>
<center>
<table bgcolor=ivory width="80%" border=1>
<tr><td>
<pre>
main()
{
float pi = 3.142; // Usual location for variable definitions
cout << "PI is " << pi << endl;
int Count = 1; // C++ allows us to place a definition here.
while (Count < 10)
{
cout << Count << endl;
}
}
</pre>
</td></tr>
</table>
</center>
<p>
It should be noted that <b>Count</b> is only in scope (usable) from the
point of definition and to the end of the block.
It can not be used in the previous <b>cout</b> statement.
<p>
The idea of this feature is to allow you to put variable declarations
near to the place
you wish to use them. Personnaly, I feel this should not be neccasary
if you write small concise functions....
There is one natty feature of this facility though. Check this
example out.
<p>
<center>
<table bgcolor=ivory width="80%" border=1>
<tr><td>
<pre>
main()
{
int Last = 10;
while (int Count; Count < Last; Count++)
{
cout << Count << endl;
}
}
</pre>
</td></tr>
</table>
</center>
<p>
In this example, <b>Count</b> is defined inside the <b>for</b>
statement and only exists while the for block is being executed.
<p>
<hr>
<h2>Examples:</h2>
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<hr>
<h2>See Also:</h2>
</font>
<hr>
<font color=black>
<h2>C References</h2>
<p>
<img src="../../GRAPHICS/whiteball.gif" alt="o">
<a href=../../C/SYNTAX/glo_int_vars.html> C local variables</a>
<p>
<img src="../../GRAPHICS/whiteball.gif" alt="o">
<a href="../../C/CONCEPT/data_types.html">data types</a>.
</font>
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<p>
<hr>
<font color=brown>
<address>Martin Leslie
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