[scala-bts] #2138: NamespaceBinding does not define an "equals" method

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Reporter: dcsobral | Owner: scala-xml_team
Type: defect | Status: new
Priority: normal | Component: XML support
Keywords: Namespace |
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When generating strings for an XML, each element has its scope -- a
NamespaceBinding object -- compared to that of its parent. If they aren't
equal, a namespace is added to the string representation of that element.

Unfortunately, NamespaceBinding does define an "equals" method, which
means reference equality is used, with unfortunate consequences. Any code
that does not cache Namespaces will end up producing XMLs which repeat the
namespace.

NamespaceBinding is composed of two strings and a NamespaceBinding, so an
equals method can be trivially defined for it.