if allocs != 0 {
				t.Errorf("allocation occurred during write")
			}
			// Check that buffer has correct data.
			if !Equal(buf.Bytes()[0:startLen-readBytes], xBytes[readBytes:]) {
				t.Errorf("bad initial data at %d %d", startLen, growLen)
			}
			if !Equal(buf.Bytes()[startLen-readBytes:startLen-readBytes+growLen], yBytes) {
				t.Errorf("bad written data at %d %d", startLen, growLen)
			}
		}
	}
}

Any value of comparable type may be canonicalized with the new
`Make[T]` function, which produces a reference to a canonical copy of
the value in the form of a `Handle[T]`.
Two `Handle[T]` are equal if and only if the values used to produce the
handles are equal, allowing programs to deduplicate values and reduce
their memory footprint.
Comparing two `Handle[T]` values is efficient, reducing down to a simple

<p>
Comparison operators compare two operands and yield an untyped boolean value.
</p>

<pre class="grammar">
==    equal
!=    not equal
&lt;     less
&lt;=    less or equal
&gt;     greater
&gt;=    greater or equal
</pre>

<p>
In any comparison, the first operand
must be <a href="#Assignability">assignable</a>
to the type of the second operand, or vice versa.