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<span>throw</span>
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<h1>throw</h1>
<p>The <tt>throw</tt> runtime statement permits you to generate your own <a href="../../../Additional_Information/Errors/Runner_Errors.htm">runtime exceptions</a>, ending the game and showing an error message, using the following syntax:</p>
<p class="code">throw (<expression>);</p>
<p>The expression used can be a value or a string or any other data type, and this will then generate an exception error which is - by default - shown on the screen and on closing the error message the game will end. For example calling this:</p>
<p class="code">throw ("Hello World!");</p>
<p>will cause the following unhandled exception error to be shown:</p>
<p><img alt="Unhandled runtime exception error message example" class="center" src="../../../assets/Images/Scripting_Reference/GML/Overview/ThrowUnhandledMessage.png"/>You can, however, take over this error message and use your own handler code by calling
the function <a href="../../GML_Reference/Debugging/exception_unhandled_handler.htm"><tt>exception_unhandled_handler()</tt></a>. This <a href="../Runtime_Functions.htm">runtime function</a> permits you to supply a custom <a href="../Method_Variables.htm">method</a> to use that will be called whenever any unhandled exceptions occur in your game.</p>
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