Checklist

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  for similar or identical bug reports.
• I have checked the pull requests list
  for existing proposed fixes.
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Related Issues and Possible Duplicates

Related Issues

• None

Possible Duplicates

• None

Description

In the last sentence of the CallBack section, it's mentioned that:

As expected this will first launch one task calculating 2 + 2, then another task calculating 8 + 4.

But it should be 4 + 8 since the result of the parent task is supposed to be "prepended" to the arguments of the signature.

Suggestions

Change 8 + 4 to 4 + 8.

Of course it doesn't have effect in the add task, but it will with other tasks that the order matters.