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@@ -5736,17 +5736,17 @@ The way around this problem is to include information about a value's
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runtime type in the value itself, so that this information can be
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inspected by operators such as \code{not}. In particular, we shall
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steal the 3 right-most bits from our 64-bit values to encode the
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-runtime type. We shall use $000$ to identify integers, $001$ for
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-Booleans, $010$ for vectors, $011$ for procedures, and $100$ for the
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+runtime type. We shall use $001$ to identify integers, $100$ for
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+Booleans, $010$ for vectors, $011$ for procedures, and $101$ for the
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void value. We shall refer to these 3 bits as the \emph{tag} and we
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define the following auxilliary function.
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\begin{align*}
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-\itm{tagof}(\key{Integer}) &= 000 \\
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-\itm{tagof}(\key{Boolean}) &= 001 \\
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+\itm{tagof}(\key{Integer}) &= 001 \\
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+\itm{tagof}(\key{Boolean}) &= 100 \\
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\itm{tagof}((\key{Vector} \ldots)) &= 010 \\
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\itm{tagof}((\key{Vectorof} \ldots)) &= 010 \\
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\itm{tagof}((\ldots \key{->} \ldots)) &= 011 \\
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-\itm{tagof}(\key{Void}) &= 100
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+\itm{tagof}(\key{Void}) &= 101
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\end{align*}
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(We shall say more about the new \key{Vectorof} type shortly.)
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This stealing of 3 bits comes at some
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Jeremy Siek