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I discovered a bug in Alice 3.8 when demoing something in class yesterday. Some students experienced it in class as well. It happens on both Mac and Windows.
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<div class="">The bug occurs when creating a scene procedure with a parameter. If the procedure is already in use, it has to be updated, OK. If you try to drag another invocation of the procedure, the drop sometimes generates an AssertionError. The Queen pops
up. The drag and drop action is interrupted. I tell students to save and relaunch Alice. Nothing bad seems to happen after.</div>
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<div class="">Here are the steps to reproduce the error:</div>
<div class="">1. Launch Alice. Create a new scene.
<div style="margin: 0px; font-stretch: normal; line-height: normal;" class="">2. Add a scene procedure.</div>
<div style="margin: 0px; font-stretch: normal; line-height: normal;" class="">3. Switch back to myFirstMethod and call the new procedure.</div>
<div style="margin: 0px; font-stretch: normal; line-height: normal;" class="">4. Switch back to the new procedure and add a parameter. Tick the box "I understand I need to update the invocations to this procedure."</div>
<div style="margin: 0px; font-stretch: normal; line-height: normal;" class="">5. Switch back to myFirstMethod.</div>
<div style="margin: 0px; font-stretch: normal; line-height: normal;" class="">6. Fix the invocation (or not, it doesn't matter)</div>
<div style="margin: 0px; font-stretch: normal; line-height: normal;" class="">7. Drag a new invocation of the procedure, and drop it _above_ the existing procedure invocation.</div>
<div style="margin: 0px; font-stretch: normal; line-height: normal;" class="">This generates an "Assertion Error."</div>
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I have been using this same process for teaching parameters for years in Alice 3 without encountering this issue, so I think it is new to version 3.8. I filed the bug report within the Alice environment.</div>
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James</div>
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<font face="Arial" class="">—<br class="">
<b class="">James Vanderhyde<br class="">
</b>Associate Professor<br class="">
Computer Science<br class="">
Saint Xavier University<br class="">
3700 W. 103rd St.<br class="">
Chicago, IL 60655<br class="">
773-298-3454</font></div>
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<font face="Arial" class=""><a href="mailto:vanderhyde@sxu.edu" class="">vanderhyde@sxu.edu</a></font></div>
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<font face="Arial" class=""><a href="http://sxu.edu" class="">sxu.edu</a></font></div>
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