Re: How compiler detects forward reference errors

[Stefan Koch via Digitalmars-d-learn]

On Saturday, 3 September 2016 at 14:06:06 UTC, Igor wrote:

Can anyone explain in plain English how does compiler process and detect a "test.d(6) Error: forward reference of variable a" in following code:

import std.stdio;

enum a = 1 + b;
enum d = 5 + a; // No error here
enum b = 12 + c;
enum c = 10 + a; // error here

void main()
{
    writeln("Hello World!", b);
}

This is an recursive expression.
c = 10 + 1 + 12 + c ...
and therefore cannot be compiled.