View source for Tracing until a value change or until a value match

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<span class="f_Para">Another tracing option lets you step through a program, stopping on each statement that changes a specified data item. In this case, both the statement that modified the item and the resulting value are shown in the </span><var>Execution Trace</var><span class="f_Para"> tab. </span>

<span class="f_Para">To trace until a variable value changes:</span>

: 1. <span class="f_ListNum1">Enter a variable or data item name in the </span><span class="f_ListBul1">[[Entity name input box|Entity name input box]]</span><span class="f_ListNum1"> below the main window. </span>

:: '''Note:'''<span class="f_ListNote"> Items like global variables or </span> <var>Model 204</var><span class="f_ListNote"> fields or parameters require the additional prefixes before their names that are described in [[Viewing and modifying program elements|Viewing and modifying program elements.]] </span>

: 2. <span class="f_ListNum1">Click the </span><var>Run to Change</var><span class="f_ListNum1"> button: </span>

: [[File:tracebut4b_zoom60.gif|281x167px|traceBut4b]]
:: The request runs until the specified item is modified.  
:: If the value of the item does not change, execution runs until the end of the request or one of the events listed in [[Tracing all lines executed|&quot;Tracing all lines executed.&quot;]] 

: 3. <span class="f_ListNum1">View the result in the </span><var>Execution Trace</var><span class="f_ListNum1"> page. </span>
:: If the request contains further changes to the value, you can click <span class="f_ListNum1">the </span><vav>Run to Change</var><span class="f_ListNum1"> button again, or you can </span><span class="f_ListContinue">press the Enter key (which repeats the </span><span class="term">Run to Change</span><span class="f_ListContinue"> action whenever the </span><span class="term">Run to Change</span><span class="f_ListContinue"> button is highlighted. </span>
:: The </span><span class="f_Monospace">[[runUntilVariableChanges command|runUntilVariableChanges]]</span><span class="f_ListContinue"> mappable command and the </span><span class="term">Run Until Variable Changes </span><span class="f_ListNum1">option</span><span class="f_ListContinue"> in the </span><span class="f_ListNum1">Client's </span><var>Execution</var><span class="f_ListNum1"> menu </span><span class="f_ListContinue">have the same effect as the </span><var>Run To Change</var><span class="f_ListNum1"> </span><span class="f_ListContinue">button. </span>

<span id="tracevareqval" class="hmanchor"></span><span class="f_Para">A variation of the &quot;tracing until&quot; technique lets you continue a request's execution until </span><span class="f_ListContinue">a selected item's value is equal to a value</span><span class="f_Para"> you specify. For example, you may want to use this feature to verify that a variable does not ever become a certain value. </span>

<span class="f_Para">To trace until a particular data item value:</span>

: 1. <span class="f_ListNum1">Enter the item name (prefixed if necessary) in the </span><span class="f_Para">Entity name input</span><span class="f_ListBul1"> box.</span>

: 2. <span class="f_ListNum1">Press the Alt key while clicking the </span><var>Run to Change</var><span class="f_ListNum1"> button. </span>
:: The <span class="f_Monospace">[[traceUntilVariableEqualsValue command|traceUntilVariableEqualsValue]]</span><span class="f_ListContinue"> mappable command and the </span><span class="term">Trace Until Variable Equals Value </span><span class="f_ListNum1">option</span><span class="f_ListContinue"> in the </span><span class="f_ListNum1">Client's </span><var>Execution</var><span class="f_ListNum1"> menu </span><span class="f_ListContinue">have the same effect as the ALT-</span>var>Run To Change</var><span class="f_ListNum1"> </span><span class="f_ListContinue">button. </span>

: 3. <span class="f_ListNum1">In the </span><var>Tracing</var><span class="f_ListNum1"> dialog box, specify the value of the variable at which tracing will stop: </span>

: [[File:traceuntil_zoom50.gif|387x93px|traceUntil]]<span class="f_ListContinue"> </span>

: 4. <span class="f_ListNum1">Click the </span><var>Trace</var><span class="f_ListNum1"> button, at the right. </span>
:: The request will run until the statement that makes the value of the selected item equal to the value you just specified, or the request will run <span class="f_Para">until the end of the request or one of the events listed in [[Tracing all lines executed|&quot;Tracing all lines executed&quot;]]</span><span class="f_ListContinue">.  </span>

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