From a97c8e56362b77fcbbf5b57e5053356320273977 Mon Sep 17 00:00:00 2001 From: Tom Tromey Date: Fri, 10 May 2019 08:19:04 -0600 Subject: [PATCH] Document lazy computation for pretty-printer "children" method I found out recently that some users didn't know that the Python pretty-printers "children" method should compute its result lazily. This has been a good idea since the earliest days, but wasn't mentioned in the docs. This patch adds some text to this effect. gdb/doc/ChangeLog 2019-05-10 Tom Tromey * python.texi (Pretty Printing API): Mention lazy computation for "children". --- gdb/doc/ChangeLog | 5 +++++ gdb/doc/python.texi | 6 ++++++ 2 files changed, 11 insertions(+) diff --git a/gdb/doc/ChangeLog b/gdb/doc/ChangeLog index d05b5a381a3..fe7f33ba7bf 100644 --- a/gdb/doc/ChangeLog +++ b/gdb/doc/ChangeLog @@ -1,3 +1,8 @@ +2019-05-10 Tom Tromey + + * python.texi (Pretty Printing API): Mention lazy computation for + "children". + 2019-05-10 Tom Tromey * gdb.texinfo (Set Catchpoints): Add text for parameter to "catch diff --git a/gdb/doc/python.texi b/gdb/doc/python.texi index b47c38deef7..98e52bb770c 100644 --- a/gdb/doc/python.texi +++ b/gdb/doc/python.texi @@ -1371,6 +1371,12 @@ object which is convertible to a @value{GDBN} value. This method is optional. If it does not exist, @value{GDBN} will act as though the value has no children. +For efficiency, the @code{children} method should lazily compute its +results. This will let @value{GDBN} read as few elements as +necessary, for example when various print settings (@pxref{Print +Settings}) or @code{-var-list-children} (@pxref{GDB/MI Variable +Objects}) limit the number of elements to be displayed. + Children may be hidden from display based on the value of @samp{set print max-depth} (@pxref{Print Settings}). @end defun -- 2.30.2