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vivekjvs
Frequent Visitor

Take input as list which can be null

Hi

 

I have a parameter of type list that can be null. Here is the code-

 

(a as list)=>
    let 
        b = if a is null then {""} else a
    in 
        b

 

And I am invoking the above function like this-

 

let
    Source = Query1(null)
in
    Source

 

The error I get if I run the above query-

 

Expression.Error: We cannot convert the value null to type List.
Details:
    Value=
    Type=[Type]

 


Can someone please tell me how I can pass null to a parameter of type list.

Thanks
Vivek

1 REPLY 1
Fowmy
Super User
Super User

@vivekjvs 

Your function expects list as input that's why the error comes up. Provide the value as follows

 

 

let
    Source = Query1({null})
in
    Source

 

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