9.1

book.tex

@@ -16735,8 +16735,6 @@ class InterpLdyn(InterpLlambda):
 
 \section{Representation of Tagged Values}
 
-\python{UNDER CONSTRUCTION}
-
 The interpreter for \LangDyn{} introduced a new kind of value, a tagged
 value. To compile \LangDyn{} to x86 we must decide how to represent tagged
 values at the bit level. Because almost every operation in \LangDyn{}
@@ -16746,6 +16744,7 @@ the 3 right-most bits to encode the tag.  We use $001$ to identify
 integers, $100$ for Booleans, $010$ for vectors, $011$ for procedures,
 and $101$ for the void value. We define the following auxiliary
 function for mapping types to tag codes.
+{\if\edition\racketEd
 \begin{align*}
 \itm{tagof}(\key{Integer}) &= 001 \\
 \itm{tagof}(\key{Boolean}) &= 100 \\
@@ -16753,6 +16752,16 @@ function for mapping types to tag codes.
 \itm{tagof}((\ldots \key{->} \ldots)) &= 011 \\
 \itm{tagof}(\key{Void}) &= 101
 \end{align*}
+\fi}
+{\if\edition\pythonEd
+\begin{align*}
+\itm{tagof}(\key{IntType()}) &= 001 \\
+\itm{tagof}(\key{BoolType()}) &= 100 \\
+\itm{tagof}(\key{TupleType(ts)}) &= 010 \\
+\itm{tagof}(\key{FunctionType(ps, rt)}) &= 011 \\
+\itm{tagof}(\key{type(None)}) &= 101
+\end{align*}
+\fi}
 This stealing of 3 bits comes at some price: our integers are reduced
 to ranging from $-2^{60}$ to $2^{60}$. The stealing does not adversely
 affect vectors and procedures because those values are addresses, and
@@ -16762,15 +16771,18 @@ the rightmost 3 bits with the tag and we can simply zero-out the tag
 to recover the original address.
 
 To make tagged values into first-class entities, we can give them a
-type, called \code{Any}, and define operations such as \code{Inject}
-and \code{Project} for creating and using them, yielding the \LangAny{}
-intermediate language. We describe how to compile \LangDyn{} to \LangAny{} in
-Section~\ref{sec:compile-r7} but first we describe the \LangAny{} language
-in greater detail.
+type, called \racket{\code{Any}}\python{AnyType}, and define operations
+such as \code{Inject} and \code{Project} for creating and using them,
+yielding the \LangAny{} intermediate language. We describe how to
+compile \LangDyn{} to \LangAny{} in Section~\ref{sec:compile-r7}
+but first we describe the \LangAny{} language in greater detail.
 
 \section{The \LangAny{} Language}
 \label{sec:Rany-lang}
 
+\python{UNDER CONSTRUCTION}
+
+
 \newcommand{\LAnyAST}{
 \begin{array}{lcl}
 \Type &::= & \key{Any} \\