Extract every string occurrence with additional characters

[BizyB]

hello experts

have just begun having fun with the powerBI and have hit the below roadblock although sounds simple. please guide me where am going wrong!

problem statement: 

am trying to extract a set of strings based on a common pattern with no specific delimiter in place from a column within a table separated by columns

example:

Column1	Expected result
AD1234 AD9833: This is sample data	AD1234, AD9833
AD6835,AD0978 This is sample data	AD6835, AD0978

Formula am trying to use:

Text.Combine(
  List.Select(
    Text.PositionOf([Column1], "AD", Occurrence.All),
    each Text.Middle([Column1], _, 6)
  ),
  ", "
)

Am receiving the following error

Expression.Error: We cannot apply field access to the type Number.
Details:
    Value=0
    Key=summary

[watkinnc]

Why not just use this in your Table.AddColumn:

each Text.Combine({Text.Range([Column1], 0, 6), Text.Range([Column1], 8, 6)}, ", ")

Simpler, plus what if it's ever something besides "AD"?

--Nate

[BizyB]

thanks @watkinnc and apologies for coming back to you late on this. 

the trouble with the Column1 data is that it is manually documented by hundreds of users with just a guideline and no control. So the position of "AD" is not static. Also the delimiter is not constant as well because of the varying user inputs.

Because of the above conditions, think the solution from @ronrsnfld works better. Also currently we are just focused on getting AD. Anything besides "AD" that comes in later will have to be dealt with it accordingly later on.. so not worries about it now 🙂

thank you!

[BizyB]

wonderful.. thanks a lot for the tip.. that worked like a charm!

[ronrsnfld · Accepted solution]

I suggest:

in the Advanced Editor:

#"Added Custom" = Table.AddColumn(Source, "Extract", each Text.Combine(
                List.Accumulate(
                    Text.PositionOf([Column1], "AD", Occurrence.All),
                    {},
                    (s,c)=> s & {Text.Middle([Column1],c,6)}),", "), type text)

or in the UI:

Text.Combine(
    List.Accumulate(
        Text.PositionOf([Column1], "AD", Occurrence.All),
        {},
        (s,c)=> s & {Text.Middle([Column1],c,6)}),
    ", ")