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Dicken
Continued Contributor
Continued Contributor

Power Query Custom Function dialog box



Hi, 
is there a way you can select a list via the function dialog box,   

so if I have a function;  SufF;   
let
sumlist = (x)=> List.Sum( x )
in
sumlist

and a list = "alist"   = {2,2,2,2,2}   

In can just use   ; SumF( alist) or 
Function.Invoke( SumF,
{alist} )

but the only way I have been able to use the functon dialog box is convert list to table, 
then  define x as a list sumlist = (x as list )=> List.Sum( x )
and then select the column to be treated as a list, is there a wat to access the list in the function dialog box directly? 

Richard 


2 ACCEPTED SOLUTIONS
lbendlin
Super User
Super User

Functions need parameters.  Parameters in the "function dialogue"  can only be of basic type (plus binary)

 

lbendlin_0-1741541921109.png

 

So this will work

 

let
alist = {2,2,2,2,2},
SumF = (x) => List.Sum(x)
in
SumF(alist)

 

but it won't work if your alist is a parameter, even if that parameter is "list of values".

 

Apart from the academic aspect - is there a business problem you are trying to solve? You may have to dive deep into Expression.Evaluate().

View solution in original post

Dicken
Continued Contributor
Continued Contributor

No, I was just interested to see if there was some trick I was overlooking , 
thanks anyway .

Richard. 

View solution in original post

2 REPLIES 2
lbendlin
Super User
Super User

Functions need parameters.  Parameters in the "function dialogue"  can only be of basic type (plus binary)

 

lbendlin_0-1741541921109.png

 

So this will work

 

let
alist = {2,2,2,2,2},
SumF = (x) => List.Sum(x)
in
SumF(alist)

 

but it won't work if your alist is a parameter, even if that parameter is "list of values".

 

Apart from the academic aspect - is there a business problem you are trying to solve? You may have to dive deep into Expression.Evaluate().

Dicken
Continued Contributor
Continued Contributor

No, I was just interested to see if there was some trick I was overlooking , 
thanks anyway .

Richard. 

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