[Emacs-diffs] fix/bug-31311-pcase-doc 5fc0f24 11/16: mention unsuitability of ‘t’, ‘nil’ as SYMBOL pattern

[Thien-Thi Nguyen]

branch: fix/bug-31311-pcase-doc
commit 5fc0f24cc39a99670d42efbdd018384552e3cc19
Author: Thien-Thi Nguyen <address@hidden>
Commit: Thien-Thi Nguyen <address@hidden>

    mention unsuitability of ‘t’, ‘nil’ as SYMBOL pattern
---
 doc/lispref/control.texi | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/doc/lispref/control.texi b/doc/lispref/control.texi
index 6fffe5e..b53e9ca 100644
--- a/doc/lispref/control.texi
+++ b/doc/lispref/control.texi
@@ -409,6 +409,10 @@ Matches any @var{expval}, and additionally let-binds 
@var{symbol} to
 @c        - Move all idioms and examples out of table.
 @c        Probably latter is best.
 
+Two symbols to avoid are @code{t}, which behaves like @code{_}
+(above) and is deprecated, and @code{nil}, which signals error.
+It makes no sense to bind these (@pxref{Constant Variables}).
+
 @item (pred @var{predfun})
 Matches if the predicate function @var{predfun} returns address@hidden
 when called on @var{expval}.