help/info/for.html

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  19 <title>for</title>
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  37 <hr>
  38 <h1>for</h1>
  39 <hr align="left" width="75%">
  40 <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
  41 is reached.</p>
  42 <ul>
  43   <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>
  44 </ul>
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  51     <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"
  52       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>)
  53     {</b></font>&nbsp;<i> statement_block </i><font face="Courier New" color="#003258" size="5"><b>};</b></font></h3>
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  58 </div>
  59 <ul>
  60   <li>
  61   <p>The <font face="Courier New" color="#003258" size="4"><b>for</b></font> keyword introduces the loop.</p>
  62   </li>
  63   <li>
  64   <p><i>index_variable_declaration</i> is optional. When used, the variable will only be visible within the loop.</p>
  65   </li>
  66   <li>
  67   <p><i>initial_value</i> is used to initialize the index (or counter) variable of the loop.</p>
  68   </li>
  69   <li>
  70   <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>
  71   </li>
  72   <li>
  73   <p><i>manipulator_expression</i> is stepping the index variable after each new loop iteration.</p>
  74   </li>
  75   <li>
  76   <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>
  77   </li>
  78 </ul>
  79 <hr align="left" width="50%">
  80 <p>Example 1:
  81 <p><font face="Courier New">var integer j;&nbsp;<br>
  82 for (j:=1; j&lt;=10; j:= j+2) { log (&quot;index variable: &quot;, j) }<br>
  83 </font>
  84 <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
  85 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
  86 five lines in the log.</p>
  87 <hr align="left" width="25%">
  88 <p>Example 2:
  89 <p><font face="Courier New">for (var integer jj:=1; jj&lt;=10; jj:= jj+2) { log (&quot;index variable: &quot;, jj) }<br>
  90 </font>
  91 <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>
  92 <hr align="left" width="25%">
  93 <hr align="left" width="25%">
  94 <p><a HREF="BNF.html#forstatement">BNF definition</a> of <font face="Courier New">for</font></p>
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