From 10d20600bf4c994b053af1fbabec8b2311d7063d Mon Sep 17 00:00:00 2001
From: Emery Hemingway <ehmry@posteo.net>
Date: Sun, 11 Jun 2023 21:24:10 +0100
Subject: [PATCH] Escape zero-length Symbols

---
 src/preserves.nim | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/src/preserves.nim b/src/preserves.nim
index c3de9b5..a788589 100644
--- a/src/preserves.nim
+++ b/src/preserves.nim
@@ -27,14 +27,16 @@ const
   compoundKinds* = {pkRecord, pkSequence, pkSet, pkDictionary}
 
 type Symbol* = distinct string
-proc `$`*(s: Symbol): string {.borrow.}
 proc `<`*(x, y: Symbol): bool {.borrow.}
 proc `==`*(x, y: Symbol): bool {.borrow.}
 proc hash*(s: Symbol): Hash {.borrow.}
 proc len*(s: Symbol): int {.borrow.}
 
+proc `$`*(s: Symbol): string =
+  if s.len == 0: "||" else: string(s)
+
 type
-  Preserve*[E = void] = object
+  Preserve*[E] = object
     embedded*: bool
       ## Flag to mark embedded Preserves
     case kind*: PreserveKind