--- a/calc.tcl	Wed Feb 17 10:29:06 2021 +0200
+++ b/calc.tcl	Wed Feb 17 10:29:41 2021 +0200
@@ -31,6 +31,7 @@
   putserv "$calc_preferredmsg $udest :$umsg"
 }
 
+
 # ------------------------------------------------------------------------
 proc calc_do {args} {
 
@@ -55,7 +56,7 @@
   }
 
   set result [calc_do $args]
-  calc_smsg $chan "$nick, $result"
+  calc_smsg $chan "${nick}, ${result}"
   return 1
 }