// injects the namespace mapping at the top
private void _injectMapping(XmlNamespaceMap mapping) {
if (!StronglyTyped) return;
var buffer = new TextBuffer(this);
buffer.Indent();
buffer.BeginClause(BplJsonParser.NAMESPACE_ATTR);
buffer.Indent("{");
var pairs = mapping.ToArray();
for (int i = 0, N = pairs.Length; i < N; i++) {
buffer.BeginClause(pairs[i].Item1);
buffer.Append(Quote(pairs[i].Item2.ToString()));
buffer.EndClause(i == N - 1);
}
buffer.Outdent("}");
buffer.EndClause(false);
var k = 1;
if (PrettyPrint) k += NewLineChars.Length;
_output.Insert(k, buffer.ToString());
}