Bug #1389673: document correct return value of set methods
diff --git a/Doc/lib/libstdtypes.tex b/Doc/lib/libstdtypes.tex
index c0069e1..bf96a19 100644
--- a/Doc/lib/libstdtypes.tex
+++ b/Doc/lib/libstdtypes.tex
@@ -1261,17 +1261,17 @@
\begin{tableiii}{c|c|l}{code}{Operation}{Equivalent}{Result}
\lineiii{\var{s}.update(\var{t})}
{\var{s} |= \var{t}}
- {return set \var{s} with elements added from \var{t}}
+ {update set \var{s}, adding elements from \var{t}}
\lineiii{\var{s}.intersection_update(\var{t})}
{\var{s} \&= \var{t}}
- {return set \var{s} keeping only elements also found in \var{t}}
+ {update set \var{s}, keeping only elements found in both \var{s} and \var{t}}
\lineiii{\var{s}.difference_update(\var{t})}
{\var{s} -= \var{t}}
- {return set \var{s} after removing elements found in \var{t}}
+ {update set \var{s}, removing elements found in \var{t}}
\lineiii{\var{s}.symmetric_difference_update(\var{t})}
{\var{s} \textasciicircum= \var{t}}
- {return set \var{s} with elements from \var{s} or \var{t}
- but not both}
+ {update set \var{s}, keeping only elements found in either \var{s} or \var{t}
+ but not in both}
\hline
\lineiii{\var{s}.add(\var{x})}{}