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Stack Overflows in Power Query

Chris Webb hits an error:

If you’re writing your own M code in Power Query in Power BI or Excel you may run into the following error:

Expression.Error: Evaluation resulted in a stack overflow and cannot continue.

If you’re a programmer you probably know what a stack overflow is; if you’re not you might search for the term, find this Wikipedia article and still have no clue what has happened. Either way it may still be difficult to understand why you’re running into it in Power Query. To explain let’s see some examples.

Read on to learn what a stack overflow is, how you can create one, and circumstances in which one might arise in Power Query and M. Now Chris has me thinking about tail call recursion this early in the morning.