When two domains alias the same name (or one aliases another), display a
meaningful error message like:
    Failed to alias domain 'foo' as 'bar', name already taken by
    domain 'baz'.
		
	
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| .. | ||
| Makefile | ||
				When two domains alias the same name (or one aliases another), display a
meaningful error message like:
    Failed to alias domain 'foo' as 'bar', name already taken by
    domain 'baz'.
		
	
					 | 
			||
|---|---|---|
| .. | ||
| Makefile | ||