From f59ca2736dac0e544c11aaca431408931d3e21de Mon Sep 17 00:00:00 2001
From: Felix Krause <flyx@isobeef.org>
Date: Fri, 27 Jun 2014 16:57:01 +0200
Subject: [PATCH 1/2] Fixed `==` for PTables, added test.

---
 lib/pure/collections/tables.nim | 7 +++++--
 tests/table/ptables.nim         | 9 +++++++++
 2 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/lib/pure/collections/tables.nim b/lib/pure/collections/tables.nim
index ce9df09e10..146cb76c9a 100644
--- a/lib/pure/collections/tables.nim
+++ b/lib/pure/collections/tables.nim
@@ -246,7 +246,8 @@ template equalsImpl() =
     # different insertion orders mean different 'data' seqs, so we have
     # to use the slow route here:
     for key, val in s:
-      if not hasKey(t, key): return false
+      # prefix notation leads to automatic dereference in case of PTable
+      if not t.hasKey(key): return false
       if t[key] != val: return false
     return true
   
@@ -332,7 +333,9 @@ proc `$`*[A, B](t: PTable[A, B]): string =
   dollarImpl()
 
 proc `==`*[A, B](s, t: PTable[A, B]): bool =
-  equalsImpl()
+  if isNil(s): result = isNil(t)
+  elif isNil(t): result = false
+  else: equalsImpl()
 
 proc newTableFrom*[A, B, C](collection: A, index: proc(x: B): C): PTable[C, B] =
   ## Index the collection with the proc provided.
diff --git a/tests/table/ptables.nim b/tests/table/ptables.nim
index ec52d08c33..79a9aab171 100644
--- a/tests/table/ptables.nim
+++ b/tests/table/ptables.nim
@@ -104,6 +104,15 @@ block countTableTest1:
 block SyntaxTest:
   var x = newTable[int, string]({:})
 
+block nilTest:
+  var i, j: PTable[int, int] = nil
+  assert i == j
+  j = newTable[int, int]()
+  assert i != j
+  assert j != i
+  i = newTable[int, int]()
+  assert i == j
+
 proc orderedTableSortTest() =
   var t = newOrderedTable[string, int](2)
   for key, val in items(data): t[key] = val

From 18003ff1966fc54ed1b2b39988dda6961ce35c80 Mon Sep 17 00:00:00 2001
From: Clay Sweetser <clay.sweetser@gmail.com>
Date: Thu, 24 Jul 2014 18:17:20 -0400
Subject: [PATCH 2/2] Added stylistic consistancy.

---
 lib/pure/collections/tables.nim | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/pure/collections/tables.nim b/lib/pure/collections/tables.nim
index 146cb76c9a..dcf2ab4811 100644
--- a/lib/pure/collections/tables.nim
+++ b/lib/pure/collections/tables.nim
@@ -335,7 +335,7 @@ proc `$`*[A, B](t: PTable[A, B]): string =
 proc `==`*[A, B](s, t: PTable[A, B]): bool =
   if isNil(s): result = isNil(t)
   elif isNil(t): result = false
-  else: equalsImpl()
+  else: result = equalsImpl()
 
 proc newTableFrom*[A, B, C](collection: A, index: proc(x: B): C): PTable[C, B] =
   ## Index the collection with the proc provided.