From d173e9ae88380bb1217b3f775e6c3cec71a6606c Mon Sep 17 00:00:00 2001
From: Bruce Hill <bitbucket@bruce-hill.com>
Date: Wed, 24 Jan 2018 12:37:52 -0800
Subject: [PATCH] Fixed id for nil/NaN and cleaned up collection metatable
 stuff.

---
 lib/collections.nom | 34 ++++++----------------------------
 nomsu.lua           |  7 +++++++
 nomsu.moon          |  4 ++++
 3 files changed, 17 insertions(+), 28 deletions(-)

diff --git a/lib/collections.nom b/lib/collections.nom
index 1a36aae..15f27ed 100644
--- a/lib/collections.nom
+++ b/lib/collections.nom
@@ -9,10 +9,6 @@ use "lib/operators.nom"
 # List/dict functions:
 
 # Indexing
-parse [..]
-    %index st in %list, %index nd in %list, %index rd in %list
-    %index th in %list
-..as: %list -> %index
 compile [..]
     %index st to last in %list, %index nd to last in %list, %index rd to last in %list
     %index th to last in %list
@@ -47,15 +43,6 @@ compile [..]
 compile [length of %list, size of %list, size %list, number of %list, len %list] to
     "utils.size(\(%list as lua))"
 
-# Chained lookup
-compile [%list ->* %indices] to
-    assume ((%indices's "type") is "List") or barf ".."
-        Expected List for chained lookup, not \(%indices's "type")
-    %ret <- "\(%list as lua)"
-    for %index in (%indices's "value")
-        <- %ret + "[\(%index as lua)]"
-    return "\%ret"
-
 compile [append %item to %list, add %item to %list] to
     "table.insert(\(%list as lua), \(%item as lua))"
 
@@ -73,9 +60,6 @@ action [flatten %lists]
             add %item to %flat
     return %flat
 
-action [dict %items]
-    (%->1)=(%->2) for all %items
-
 action [entries in %dict]
     [{key:%k, value:%v} for %k=%v in %dict]
 
@@ -163,22 +147,16 @@ action [unique %items]
     [%k for %k=%v in (%=(yes) for all %items)]
 
 # Metatable stuff
-compile [counter] to "setmetatable({}, {__index=function() return 0; end})"
-compile [default dict] to ".."
+compile [set %dict's metatable to %metatable] to code ".."
+    setmetatable(\(%dict as lua), \(%metatable as lua));
+
+compile [new counter] to "setmetatable({}, {__index=function() return 0; end})"
+
+compile [new default dict] to ".."
     setmetatable({}, {__index=function(self, key)
         t = {};
         self[key] = t;
         return t;
     end})"
-action [chain %dict to %fallback]
-    when (type of %fallback) is ?
-        * "table"
-            =lua "setmetatable(\%dict, \%fallback)"
-        * "function"
-            =lua "setmetatable(\%dict, {__index=function(self, key) return (\%fallback)(nomsu, {['']=key, self=self}); end})"
-        * else
-            =lua "setmetatable(\%dict, {__index=function(self, key) return (\%fallback); end})"
-
 
 # TODO: maybe make a generator/coroutine?
-
diff --git a/nomsu.lua b/nomsu.lua
index ba6a834..88ad87f 100644
--- a/nomsu.lua
+++ b/nomsu.lua
@@ -1430,9 +1430,16 @@ do
       self.write_err = function(self, ...)
         return io.stderr:write(...)
       end
+      local NaN_surrogate = { }
+      local nil_surrogate = { }
       self.ids = setmetatable({ }, {
         __mode = "k",
         __index = function(self, key)
+          if key == nil then
+            return self[nil_surrogate]
+          elseif key ~= key then
+            return self[NaN_surrogate]
+          end
           local id = new_uuid()
           self[key] = id
           return id
diff --git a/nomsu.moon b/nomsu.moon
index 7ae6f89..0f13a3e 100755
--- a/nomsu.moon
+++ b/nomsu.moon
@@ -136,9 +136,13 @@ class NomsuCompiler
         @write = (...)=> io.write(...)
         @write_err = (...)=> io.stderr\write(...)
         -- Weak-key mapping from objects to randomly generated unique IDs
+        NaN_surrogate = {}
+        nil_surrogate = {}
         @ids = setmetatable({}, {
             __mode: "k"
             __index: (key)=>
+                if key == nil then return @[nil_surrogate]
+                elseif key != key then return @[NaN_surrogate]
                 id = new_uuid!
                 @[key] = id
                 return id