ARGB() function is not working when it is set as a field in the coloring expression.

[Mukhiddin]

When using ARGB() function in the expression and using it as field like follow:  

1.  Load data from excel following data.
   Point Pattern Value
   A ARGB(125,255,128,128) 5
   B ARGB(125,141,170,203) 10
   C ARGB(125,255,217,47) 15
   D RGB(255,0,255) 20
   E RGB(0,128,255) 20
2.  Set field "Point" as dimension, set field "Value" as measure, set "Pattern" as expression in Colors and legend>Colors(Custom)>By expression(Expression(Pattern ))

Load editor:

Result chart:

Resolution

Working as designed. 

With how the color is defined and used it is not an expression with a call to the ARGB function or RGB function
but a string that is interpreted as a css color that support color in the rgb(...) and rgba(...) format but not argb(...).