Code
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class Homu
{
	const
	const(string[string][string]) homuhomu()
	{
		return homuhomu_;
	}

private:
	string[string][string] homuhomu_;
}
----

Compile error(dmd 2.056)
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Error: forward reference to type const(string)
Error: cannot implicitly convert expression (this.homuhomu_) of type
const(immutable(char)[][string][string]) to const(string[string][string])
----