• d-bugmail puremagic.com (42/42) Jan 11 https://issues.dlang.org/show_bug.cgi?id=24334

d-bugmail puremagic.com writes:

https://issues.dlang.org/show_bug.cgi?id=24334

          Issue ID: 24334
           Summary: parameter name is ignored in invocation of struct
                    constructor with default values
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: major
          Priority: P1
         Component: dmd
          Assignee: nobody puremagic.com
          Reporter: jim balter.name

struct Foo
{
  this(int a, int b = 2, int c = 3)
  {
    imported!"std.stdio".writefln!"a=%s b=%s c=%s"(a, b, c);
  }
}

void main()
{
  auto foo = Foo(1, c: 99);
}


Expected output: a=1 b=2 c=99
Actual output: a=1 b=99 c=3

(This bug is dangerous, and quite shocking for a mature language.)

Note that the problem is only with a constructor. e.g, this works correctly:

struct Bar
{
  static void bar(int a, int b = 2, int c = 3)
  {
    imported!"std.stdio".writefln!"a=%s b=%s c=%s"(a, b, c);
  }
}

void main()
{
  Bar.bar(1, c: 99);
}

output: a=1 b=2 c=99

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