Array Unique value

Targets
1

Sunday challenge.

How can I create an ARRAY with unique value. In other langage I will use a SET. Of course I already have some solution but I’m looking for an elegant’s one (we are Sunday)

2

I’d use a dictionary. You can iterate over the entries when you need to.

2 Likes
3

some of your solution is to use the Extends method.

4

For concrete example imagine an array of color with unique colors

// Pseudo Code

Var colors() As Color
colors.Add(Color.Black)
colors.Add(Color.Red)
colors.Add(Color.Blue)
colors.Add(Color.Black)

System.DebugLog(colors.Count)

Will produce this

3

I expect to have 3 colors in my colors array : black red blue because the colors.Add(Color.Black) will not add the existing black color.

@MarkusR is it possible to Extends array add method ? may be by creating a Set class withe super Class has Array ?

5

An other application of a Set of unique value in array is retrieving letters in a string with Split

For ex. “dana brown”.Split return [“d”,“a”,“n”,“a”," “,“b”,“r”,“o”,“w”,“n”] with Set it would return [“d”,“a”,“n”,” ", “b”,“r”,“o”,“w”]

Hello @Dana_Brown :wink:

6 
Sub Pressed() Handles Pressed
  Var colors() As Color
  
  Call colors.AddUnique(Color.Black)
  Call colors.AddUnique(Color.Red)
  Call colors.AddUnique(Color.Blue)
  Call colors.AddUnique(Color.Black)
  
  System.DebugLog(colors.Count.ToString)
End Sub

Global Method in a Module
this Extends is a nice feature in Xojo.

Public Function AddUnique(Extends allColors() As Color, newColor As Color) As Boolean
  
  For Each col As Color In allColors
    If col = newColor Then Return False
  Next
  
  Call allColors.Add(newColor)
  Return True
  
End Function

may be by creating a Set class withe super Class has Array

you can not use Array as Super in your new Class.
but you can have a array in your class, sure.

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