lt;</span><span class='ident'>T</span><span class='op'>&gt;</span>
        <span class='kw'>where</span> <span class='ident'>T</span>: <span class='ident'>Mul</span><span class='op'>&lt;</span><span class='ident'>Output</span><span class='op'>=</span><span class='ident'>T</span><span class='op'>&gt;</span> <span class='op'>+</span> <span class='ident'>Copy</span> { ... }</pre>

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