How can I use WriteLn with an enum type?

Question

I'm trying to make a custom data type for days of the week but I can't get it to write it. The compiler error says this:

[Error] hours.dpr(28): Illegal type in Write/Writeln statement

program hours;

{$APPTYPE CONSOLE}

uses
  SysUtils;

type
  TypeDay = (Sun,Mon,Tue,Wed,Thu,Fri,Sat);

var day: TypeDay;

begin
     for day := Sun to Sat do
     begin
         writeln(day);
     end;
end.

It's in Delphi 7 on Windows.

Answer 1

You don't need to write Assembler for this; TypInfo include all that you need for do this (get the string associated to an enumerated value).

This code:

program hours;

{$APPTYPE CONSOLE}

uses
  SysUtils,
  TypInfo;

type
  TypeDay = (Sun,Mon,Tue,Wed,Thu,Fri,Sat);

var
  day: TypeDay;
  Str:String;

begin
     for day := Sun to Sat do begin
        Str := GetEnumName(TypeInfo(TypeDay),ord(day));
         writeln(Str);
     end;
end.

And this is the output:

Regards.

Answer 2

Tom, Writeln does not support a Enum as parameter. you must call to the Ordfunction to get the ordinal representation. if you wanna show the names of your TypeDay you can write a code like this.

program hours;

{$APPTYPE CONSOLE}

uses
  SysUtils;

type
  TypeDay     = (Sun,Mon,Tue,Wed,Thu,Fri,Sat);
const
  TypeDayStr  : Array[TypeDay] of string = ('Sun','Mon','Tue','Wed','Thu','Fri','Sat');

var day: TypeDay;

begin
     for day := Sun to Sat do
       writeln( Ord(day));

     for day := Sun to Sat do
       writeln( TypeDayStr[day]);

     Readln;
end.