https://issues.dlang.org/show_bug.cgi?id=17186

          Issue ID: 17186
           Summary: Type inference for parameters with default argument
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: enhancement
          Priority: P1
         Component: dmd
          Assignee: nobody@puremagic.com
          Reporter: doob@me.com

D supports type inference in my places, like variable declarations:

auto a = 3;

But the same thing doesn't work with parameters, neither template or regular parameters:

void foo(auto a = 3);
void foo(auto a = 3)();

Implementing this feature would allow for some function signatures to be shorter and make the language more consistent. Currently it seems like an arbitrary limitation.

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