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<title>for</title>
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<hr>
<h1>for</h1>
<hr align="left" width="75%">
<p>The keyword defines a counter loop. The value of the index variable is increased, decreased or manipulated in such a way that after a certain number of execution loops a termination criterion
is reached.</p>
<ul>
<li>The index variable can be declared in the statement header. By doing so, the scope of the index variable will be limited to the loop.</li>
</ul>
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<h3 align="center"><font face="Courier New" color="#003258" size="5"><b>for (</b></font>[ <i>index_variable_declaration</i> ]<i> initial_value</i><font face="Courier New" color="#003258"
size="5"><b>;</b></font><i> condition</i><font face="Courier New" color="#003258" size="5"><b>;</b></font><i> manipulator_expression</i><font face="Courier New" color="#003258" size="5"><b>)
{</b></font> <i> statement_block </i><font face="Courier New" color="#003258" size="5"><b>};</b></font></h3>
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<ul>
<li>
<p>The <font face="Courier New" color="#003258" size="4"><b>for</b></font> keyword introduces the loop.</p>
</li>
<li>
<p><i>index_variable_declaration</i> is optional. When used, the variable will only be visible within the loop.</p>
</li>
<li>
<p><i>initial_value</i> is used to initialize the index (or counter) variable of the loop.</p>
</li>
<li>
<p><i>condition</i>is a Boolean expression. It is checked at the beginning of each new loop iteration. If it evaluates to false, the loop terminates.</p>
</li>
<li>
<p><i>manipulator_expression</i> is stepping the index variable after each new loop iteration.</p>
</li>
<li>
<p><i>statement_block</i> contains one or more statements. The block will be executed in a loop until <i>condition</i> is true.</p>
</li>
</ul>
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<p>Example 1:
<p><font face="Courier New">var integer j; <br>
for (j:=1; j<=10; j:= j+2) { log ("index variable: ", j) }<br>
</font>
<p>The loop variable j is declared in the first line. In the second line, a loop is defined. The initial value of the index variable (j) is 1. The index variable is increased by 2 every time the
loop was executed. The loop execution terminates when the index value will have a value greater than 10. The statement block contains a log instruction, which will be executed 5 times resulting in
five lines in the log.</p>
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<p>Example 2:
<p><font face="Courier New">for (var integer jj:=1; jj<=10; jj:= jj+2) { log ("index variable: ", jj) }<br>
</font>
<p>The only difference to the first example is that the index variable (jj) now is declared within the loop. It means that it will not be visible outside the loop.</p>
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<p><a HREF="BNF.html#forstatement">BNF definition</a> of <font face="Courier New">for</font></p>
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