[Issue 23163] New: Can't use AliasSeq instance as default template argument of template function

[d-bugmail at puremagic.com]

https://issues.dlang.org/show_bug.cgi?id=23163

          Issue ID: 23163
           Summary: Can't use AliasSeq instance as default template
                    argument of template function
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: normal
          Priority: P1
         Component: dmd
          Assignee: nobody at puremagic.com
          Reporter: snarwin+bugzilla at gmail.com

As of DMD 2.100.0, the following program fails to compile:

---
alias AliasSeq(Args...) = Args;
void test(alias a = AliasSeq!(0))() {}
alias _ = test!();
---

The error message is

---
bug.d(2): Error: tuple `Args` forward declaration
---

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