[Issue 23646] New: A nastier forward reference bug

[d-bugmail at puremagic.com]

https://issues.dlang.org/show_bug.cgi?id=23646

          Issue ID: 23646
           Summary: A nastier forward reference bug
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Keywords: rejects-valid
          Severity: normal
          Priority: P1
         Component: dmd
          Assignee: nobody at puremagic.com
          Reporter: maxsamukha at gmail.com

alias aliases(a...) = a;

alias Components = Dependencies!Top;

template Dependencies(alias Component)
{
    alias Dependencies = aliases!(Top.DirectDependencies);
    // alias Dependencies = Top.DirectDependencies; // but this succeeds
}

struct Top
{
    alias DirectDependencies = aliases!();
    enum l = Components.length;
}

----
Error: template instance `onlineapp.Dependencies!(Top)` error instantiating

Moving `Components` last makes the code compile.

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