In C/AL we never had the ability for overloading a function. You know: using the same function name with a different context (parameters).
Now – YES WE CAN! It’s all pretty well described on docs:
CSV files are one of the most commonly used data sources in Power BI and Power Query/Get&Transform, and yet the documentation for the Csv.Document M function is very limited and in some cases incorrect. In this rather long post I’ll show you as many of the capabilities of this useful function as I’ve been able to discover.
I won’t be publishing the slide-deck directly, as Luc will soon publish both the slide deck, and the session recordings on Mibuso and YouTube, so you’ll be able to get your hands on that part. What I am publishing, though, should be quite enough for you to get your hands on my Azure Functions demos:
Following on from my post last week about M functions that are only available in custom data extensions, here’s a quick explanation of one of those functions: Extension.Contents().
Basically, it allows you to access the contents of any file you include in the .mez file of your custom data connector. Say you have a text file called MyTextFile.txt:
Here’s one for all you M geeks out there. If you look at the example code for custom data connectors on the Power BI custom data connectors GitHub repo it’s clear that there are several M functions that are available in custom data connectors that aren’t available in Power BI Desktop.