* Doc/libtime.tex: get rid of references to millitime() and

	millisleep(); document clock()

	* Doc/ref6.tex (section{Assignment statements}): added warning
	about overlaps in lhs of assignment (e.g. "i, x[i] = 1, 2")

1 files changed, 15 insertions, 1 deletions

diff --git a/Doc/ref/ref6.tex b/Doc/ref/ref6.tex
index b1d4572..53e6c40 100644
--- a/Doc/ref/ref6.tex
+++ b/Doc/ref/ref6.tex
@@ -190,11 +190,25 @@ target sequence, if the object allows it.
 
 \end{itemize}
 	
-(In the original implementation, the syntax for targets is taken
+(In the current implementation, the syntax for targets is taken
 to be the same as for expressions, and invalid syntax is rejected
 during the code generation phase, causing less detailed error
 messages.)
 
+WARNING: Although the definition of assignment implies that overlaps
+between the left-hand side and the right-hand side are `safe' (e.g.
+\verb@a, b = b, a@ swaps two variables), overlaps within the
+collection of assigned-to variables are not safe!  For instance, the
+following program prints \code@[0, 2]@:
+
+\begin{verbatim}
+x = [0, 1]
+i = 0
+i, x[i] = 1, 2
+print x
+\end{verbatim}
+
+
 \section{The {\tt pass} statement}
 \stindex{pass}