Sequence indexes are non-negative, not natural (0 is not a natural number).
Reported by Daniel May <mayds@ecn.purdue.edu>.
De-tabified everywhere.
diff --git a/Doc/ref/ref3.tex b/Doc/ref/ref3.tex
index 31d8fbb..bd876cc 100644
--- a/Doc/ref/ref3.tex
+++ b/Doc/ref/ref3.tex
@@ -227,7 +227,7 @@
\end{description} % Numbers
\item[Sequences]
-These represent finite ordered sets indexed by natural numbers.
+These represent finite ordered sets indexed by non-negative numbers.
The built-in function \function{len()}\bifuncindex{len} returns the
number of items of a sequence.
When the length of a sequence is \var{n}, the
@@ -1416,55 +1416,55 @@
\item[1.] If \var{x} is a class instance:
- \begin{itemize}
+ \begin{itemize}
- \item[1a.] If \var{x} has a \method{__coerce__()} method:
- replace \var{x} and \var{y} with the 2-tuple returned by
- \code{\var{x}.__coerce__(\var{y})}; skip to step 2 if the
- coercion returns \code{None}.
+ \item[1a.] If \var{x} has a \method{__coerce__()} method:
+ replace \var{x} and \var{y} with the 2-tuple returned by
+ \code{\var{x}.__coerce__(\var{y})}; skip to step 2 if the
+ coercion returns \code{None}.
- \item[1b.] If neither \var{x} nor \var{y} is a class instance
- after coercion, go to step 3.
+ \item[1b.] If neither \var{x} nor \var{y} is a class instance
+ after coercion, go to step 3.
- \item[1c.] If \var{x} has a method \method{__op__()}, return
- \code{\var{x}.__op__(\var{y})}; otherwise, restore \var{x} and
- \var{y} to their value before step 1a.
+ \item[1c.] If \var{x} has a method \method{__op__()}, return
+ \code{\var{x}.__op__(\var{y})}; otherwise, restore \var{x} and
+ \var{y} to their value before step 1a.
- \end{itemize}
+ \end{itemize}
\item[2.] If \var{y} is a class instance:
- \begin{itemize}
+ \begin{itemize}
- \item[2a.] If \var{y} has a \method{__coerce__()} method:
- replace \var{y} and \var{x} with the 2-tuple returned by
- \code{\var{y}.__coerce__(\var{x})}; skip to step 3 if the
- coercion returns \code{None}.
+ \item[2a.] If \var{y} has a \method{__coerce__()} method:
+ replace \var{y} and \var{x} with the 2-tuple returned by
+ \code{\var{y}.__coerce__(\var{x})}; skip to step 3 if the
+ coercion returns \code{None}.
- \item[2b.] If neither \var{x} nor \var{y} is a class instance
- after coercion, go to step 3.
+ \item[2b.] If neither \var{x} nor \var{y} is a class instance
+ after coercion, go to step 3.
- \item[2b.] If \var{y} has a method \method{__rop__()}, return
- \code{\var{y}.__rop__(\var{x})}; otherwise, restore \var{x}
- and \var{y} to their value before step 2a.
+ \item[2b.] If \var{y} has a method \method{__rop__()}, return
+ \code{\var{y}.__rop__(\var{x})}; otherwise, restore \var{x}
+ and \var{y} to their value before step 2a.
- \end{itemize}
+ \end{itemize}
\item[3.] We only get here if neither \var{x} nor \var{y} is a class
instance.
- \begin{itemize}
+ \begin{itemize}
- \item[3a.] If op is `\code{+}' and \var{x} is a sequence,
- sequence concatenation is invoked.
+ \item[3a.] If op is `\code{+}' and \var{x} is a sequence,
+ sequence concatenation is invoked.
- \item[3b.] If op is `\code{*}' and one operand is a sequence
- and the other an integer, sequence repetition is invoked.
+ \item[3b.] If op is `\code{*}' and one operand is a sequence
+ and the other an integer, sequence repetition is invoked.
- \item[3c.] Otherwise, both operands must be numbers; they are
- coerced to a common type if possible, and the numeric
- operation is invoked for that type.
+ \item[3c.] Otherwise, both operands must be numbers; they are
+ coerced to a common type if possible, and the numeric
+ operation is invoked for that type.
- \end{itemize}
+ \end{itemize}
\end{itemize}