From 8f291a18668f27213b17d614dc3f6c3be9c9e622 Mon Sep 17 00:00:00 2001
From: Bert Gijsbers <gijsbers@science.uva.nl>
Date: Wed, 24 Jul 2024 22:57:14 +0200
Subject: [PATCH] Elaborate on symbols and expressions and document the minus
 operator.

---
 man/icesh.pod | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/man/icesh.pod b/man/icesh.pod
index 44c9568fc..eef78edda 100644
--- a/man/icesh.pod
+++ b/man/icesh.pod
@@ -854,12 +854,19 @@ Some of the window actions require one or two I<EXPRESSION> arguments.
 
 =over
 
-=item B<EXPRESSION> ::= I<SYMBOL> | I<EXPRESSION> { C<+> | C<|> }
+=item B<EXPRESSION> ::= I<SYMBOL> | I<EXPRESSION> { C<+> | C<|> | C<-> }
 I<SYMBOL>
 
 =back
 
-Each I<SYMBOL> may be from one of the following applicable domains:
+This says that an expression is either a I<SYMBOL> or an expression
+which is combined with an operator to a I<SYMBOL>. In other words,
+an expression is a sequence of symbols, which are combined using
+operators, where an operator may be a plus, a vertical bar or a minus.
+
+Each I<SYMBOL> may be either a number or a named symbol from one of the
+following applicable domains, depending upon the context in which it is
+used:
 
 =over