Splitting a string into all possible substrings of certain length

[saturated_snail]

I have a column, [Description], with text strings of varying lengths.

eg.

DET.ASS.RR+1005177

I want to get a list of every 7 character long string contained within this string.

Expected result =

DET.ASS

ET.ASS.

T.ASS.R

.ASS.RR

ASS.RR+

SS.RR+1

S.RR+10

.RR+100

RR+1005

R+10051

+100517

1005177

Naturally my final table would end up with a list of descriptions with a list column:

DET.ASS.RR+1005177

List

I have tried List.Generate but cannot get this to work with text.

Thanks

Jamie

[Vijay_A_Verma · Accepted solution]

See the working here - Open a blank query - Home - Advanced Editor - Remove everything from there and paste the below code to test

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WcnEN0XMMDtYLCtI2NDAwNTQ3V4rViVZKTEpOSU1Lz8jMygbzDY2MTUzNzC2QOUhspdhYAA==", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [Data = _t]),
       #"Added Custom" = Table.AddColumn(Source, "Custom", each List.Generate(()=>[x=Text.Middle([Data],0,7),d=[Data],i=0], each [i]<Text.Length([d])-6, each [i=[i]+1,d=[d], x=Text.Middle([d],i,7)], each [x])),
    #"Expanded Custom" = Table.ExpandListColumn(#"Added Custom", "Custom")
in
    #"Expanded Custom"