Avoid spaces in a sum function when a variable is empty/void

I'm sure there is a way to figure out how not to put in empty fields, but here is a regex way of doing it.

You can create a formula field and put this in:

replacex(originalformulafield, "\s{2,}", " ")

This will find all instance of two or more spaces and replace it with a single space.

Hi Lorenzo

If you create an array of the field values you can then use concat to create a string, and replace to remove the commas.

let a := [article,Color,more stuff,kg,lt];
let b := concat(a);
let c := replace(b,",","")

I thought you could use the join function but this does not remove empty array elements where concat does.

This still isn't ideal, as any commas within your fields will also be removed.

Regards John

A better solution is

let a := [article,Color,more stuff,kg,lt];
let b:= a[let c := this; length(c) > 1];
let d := join(b," ")

Regards John

Or even simpler:

let a := [article,Color,more stuff,kg,lt];
let b:= join(a[!=""]," ")

Or maybe a oneliner ? 

Article + if Color then " " + Color end + if 'More stufs' then " " + 'More stufs' end + if Kg then " " + Kg end + if Lt then " " + Lt end