Txt-Substitute not in list

From Vectorlab

Function to substitute chars not present in a dynarray of char with a given char. By Orso B. Schmid

{ Orso *********************************************** }
{ substitutes chars not in array from a string. }
FUNCTION T_SubstituteNotInList(str: STRING; list: DYNARRAY[] OF CHAR; newChar: CHAR): STRING;
    VAR
        i : INTEGER;
        
    BEGIN
        i := 1;
        WHILE i <= Len(str) DO BEGIN
            IF (Pos(Copy(str, i, 1), list) = 0) THEN BEGIN
                Insert(newChar, str, i);
                Delete(str, i+1, 1)
            END;
            i := i + 1;
        END;
        
        T_SubstituteNotInList := str;
    END;