Some tweaks/cleanup on the nomsu code as well as adding variable

mangling to 'parse % as %' to make almost hygienic macros.

13 files changed, 94 insertions, 51 deletions

diff --git a/code_obj.lua b/code_obj.lua
index e8e86fa..e77af5c 100644
--- a/code_obj.lua
+++ b/code_obj.lua
@@ -17,6 +17,8 @@ Source = immutable({
     end
     if stop then
       assert(start <= stop + 1, "Invalid range: " .. tostring(start) .. ", " .. tostring(stop))
+    else
+      error("HUH?")
     end
     return filename, start, stop
   end,
diff --git a/code_obj.moon b/code_obj.moon
index 14bc74a..d764430 100644
--- a/code_obj.moon
+++ b/code_obj.moon
@@ -9,6 +9,7 @@ Source = immutable {"filename","start","stop"}, {
         if not start
             start, stop = 1, #FILE_CACHE[filename]
         if stop then assert(start <= stop+1, "Invalid range: #{start}, #{stop}")
+        else error("HUH?")
         return filename, start, stop
     from_string: (str)=>
         filename,start,stop = str\match("^(.-)%[(%d+):(%d+)%]$")
diff --git a/core/collections.nom b/core/collections.nom
index 7922a4f..81ff3d2 100644
--- a/core/collections.nom
+++ b/core/collections.nom
@@ -113,23 +113,39 @@ immediately
     parse [keys in %dict] as: %k for %k = %v in %dict
     parse [values in %dict] as: %v for %k = %v in %dict
 
+# Metatable stuff
+immediately
+    compile [set %dict's metatable to %metatable] to
+        Lua "setmetatable(\(%dict as lua expr), \(%metatable as lua expr));"
+    
+    compile [%dict with fallback %key -> %value] to
+        Lua value ".."
+            setmetatable(\(%dict as lua expr), {__index=function(self, \(%key as lua expr))
+                local value = \(%value as lua expr)
+                self[\(%key as lua expr)] = value
+                return value
+            end})
+    
+immediately
+    parse [new counter] as: {} with fallback % -> 0
+    parse [new default dict] as: {} with fallback % -> {}
+
 # Sorting
 immediately
     compile [sort %items] to: Lua "table.sort(\(%items as lua expr));"
-    compile [sort %items by %key_expr] to
-        Lua ".."
-            utils.sort(\(%items as lua expr), function(_)
-                return \(%key_expr as lua expr);
-            end);
+    parse [sort %items by %item = %key_expr] as
+        do
+            %keys <- ({} with fallback %item -> %key_expr)
+            lua> "table.sort(\%items, function(x,y) return \%keys[x] < \%keys[y] end)"
 
 immediately
     action [%items sorted, sorted %items]
         %copy <- (% for % in %items)
         sort %copy
         return %copy
-    action [%items sorted by %key]
+    action [%items sorted by %item = %key]
         %copy <- (% for % in %items)
-        sort %copy by %key
+        sort %copy by %item = %key
         return %copy
 
     action [unique %items]
@@ -141,19 +157,5 @@ immediately
                 (% in %seen) <- (yes)
         return %unique
 
-immediately
-    # Metatable stuff
-    compile [set %dict's metatable to %metatable] to
-        Lua "setmetatable(\(%dict as lua expr), \(%metatable as lua expr));"
-
-    compile [new counter] to: Lua value "setmetatable({}, {__index=function() return 0; end})"
-
-    compile [new default dict] to
-        Lua value ".."
-            setmetatable({}, {__index=function(self, key)
-                t = {};
-                self[key] = t;
-                return t;
-            end})
 
 # TODO: maybe make a generator/coroutine?
diff --git a/core/math.nom b/core/math.nom
index ed2cdb6..677230b 100644
--- a/core/math.nom
+++ b/core/math.nom
@@ -74,16 +74,22 @@ compile [min of %items, smallest of %items, lowest of %items] to
     Lua value "utils.min(\(%items as lua expr))"
 compile [max of %items, biggest of %items, largest of %items, highest of %items] to
     Lua value "utils.max(\(%items as lua expr))"
-compile [min of %items by %value_expr] to
-    Lua value ".."
-        utils.min(\(%items as lua expr), function(_)
-            return \(%value_expr as lua expr)
-        end)
-compile [max of %items by %value_expr] to
-    Lua value ".."
-        utils.max(\(%items as lua expr), function(_)
-            return \(%value_expr as lua expr)
-        end)
+parse [min of %items by %item = %value_expr] as
+    result of
+        <- {%best:nil, %best_key:nil}
+        for %item in %items
+            %key <- %value_expr
+            if: (%best = (nil)) or (%key < %best_key)
+                <- {%best:%item, %best_key:%key}
+        return %best
+parse [max of %items by %item = %value_expr] as
+    result of
+        <- {%best:nil, %best_key:nil}
+        for %item in %items
+            %key <- %value_expr
+            if: (%best = (nil)) or (%key > %best_key)
+                <- {%best:%item, %best_key:%key}
+        return %best
 
 # Random functions
 action [seed random with %]
diff --git a/core/metaprogramming.nom b/core/metaprogramming.nom
index 76ba731..717690d 100644
--- a/core/metaprogramming.nom
+++ b/core/metaprogramming.nom
@@ -86,11 +86,14 @@ immediately
                     lua:append(", ", lua_var)
                 end
             end
+            MANGLE_INDEX = (MANGLE_INDEX or 0) + 1
             local function make_tree(t)
                 if type(t) ~= 'table' and type(t) ~= 'userdata' then
                     return repr(t)
                 elseif t.type == 'Var' and replacements[t.value] then
                     return replacements[t.value]
+                elseif t.type == 'Var' then
+                    return t.type.."("..repr(t.value.."#"..tostring(MANGLE_INDEX))..", "..repr(t.source)..")"
                 elseif t.is_multi then
                     local bits = {}
                     for i, entry in ipairs(t.value) do
@@ -104,14 +107,16 @@ immediately
             lua:append(")\n    local tree = ", make_tree(\%longhand), "\n    return nomsu:tree_to_lua(tree)\nend);")
             return lua
 
-action [remove action %stub]
-    lua> ".."
-        local fn = ACTIONS[\%stub]
-        local stubs = ARG_ORDERS[fn]
-        for stub in pairs(stubs) do
-            ACTIONS[stub] = nil
+compile [remove action %action] to
+    Lua ".."
+        do
+            local fn = ACTIONS[\(=lua "repr(\%action:get_stub())")]
+            local stubs = ARG_ORDERS[fn]
+            for stub in pairs(stubs) do
+                ACTIONS[stub] = nil
+            end
+            ARG_ORDERS[fn] = nil
         end
-        ARG_ORDERS[fn] = nil
 
 immediately
     action [%tree as nomsu]
diff --git a/core/operators.nom b/core/operators.nom
index 7f5c772..c3b56c6 100644
--- a/core/operators.nom
+++ b/core/operators.nom
@@ -47,9 +47,16 @@ immediately
 # Variable assignment operator
 immediately
     compile [%var <- %value] to
-        lua> "local \%var_lua = \(%var as lua);"
+        lua> "local \%var_lua = \(%var as lua)"
         assume %var_lua.is_value or barf "Invalid target for assignment: \%var"
-        lua> "local \%value_lua = \(%value as lua);"
+        lua> ".."
+            \%value = \%value:map(function(t)
+                if Action:is_instance(t) and t:get_stub() == "?" then
+                    return \%var
+                end
+            end)
+            local \%value_lua = \(%value as lua)
+
         assume %value_lua.is_value or barf "Invalid value for assignment: \%value"
         lua> ".."
             local lua = Lua(tree.source, \%var_lua, ' = ', \%value_lua, ';')
@@ -67,6 +74,11 @@ immediately
             local lhs, rhs = Lua(tree.source), Lua(tree.source)
             for i, item in ipairs(\%assignments.value) do
                 local \%target, \%value = item.value[1], item.value[2]
+                \%value = \%value:map(function(t)
+                    if Action:is_instance(t) and t:get_stub() == "?" then
+                        return \%target
+                    end
+                end)
                 local target_lua = \(%target as lua)
                 if not target_lua.is_value then error("Invalid target for assignment: "..\(%target as text)) end
                 local value_lua = \(%value as lua)
diff --git a/examples/how_do_i.nom b/examples/how_do_i.nom
index 13517fc..5269996 100644
--- a/examples/how_do_i.nom
+++ b/examples/how_do_i.nom
@@ -17,17 +17,17 @@ use "core"
 say "Hello world!"
 
 # How do I set a variable?
-%x <- 1
+%foobar <- 1
 %str <- "Hello world"
 # Expressions that are more than just literal values require parentheses:
-%x <- (2 + 3)
+%foobar <- (2 + 3)
 %one-two <- 12
 say %one-two
 
 # How do I modify a variable?
-%x <- (%x + 1)
+%foobar <- (%foobar + 1)
 # Or, as a shorthand, you can do this to increment a variable:
-%x +<- 1
+%foobar +<- 1
 
 # How do I define a mutli-line string?
 %mutli-str <- ".."
diff --git a/nomsu.lua b/nomsu.lua
index cc95de4..fcd8d38 100644
--- a/nomsu.lua
+++ b/nomsu.lua
@@ -314,7 +314,7 @@ do
         _nomsu_chunk_counter = _nomsu_chunk_counter + 1
         local filename = "<nomsu chunk #" .. tostring(_nomsu_chunk_counter) .. ">.nom"
         FILE_CACHE[filename] = nomsu_code
-        nomsu_code = Nomsu(filename, nomsu_code)
+        nomsu_code = Nomsu(Source(filename, 1, #nomsu_code), nomsu_code)
       end
       local userdata = {
         source_code = nomsu_code,
diff --git a/nomsu.moon b/nomsu.moon
index 7d9a2bb..1da214b 100755
--- a/nomsu.moon
+++ b/nomsu.moon
@@ -325,7 +325,7 @@ class NomsuCompiler
             _nomsu_chunk_counter += 1
             filename = "<nomsu chunk ##{_nomsu_chunk_counter}>.nom"
             FILE_CACHE[filename] = nomsu_code
-            nomsu_code = Nomsu(filename, nomsu_code)
+            nomsu_code = Nomsu(Source(filename,1,#nomsu_code), nomsu_code)
 
         userdata = {
             source_code:nomsu_code, indent: 0, errors: {},
diff --git a/nomsu.peg b/nomsu.peg
index e5f6c56..90becb7 100644
--- a/nomsu.peg
+++ b/nomsu.peg
@@ -88,7 +88,7 @@ number (Number): (("-"? (([0-9]+ "." [0-9]+) / ("." [0-9]+) / ([0-9]+)))-> tonum
 
 -- Variables can be nameless (i.e. just %) and can't contain operators like apostrophe
 -- which is a hack to allow %'s to parse as "%" and "' s" separately
-variable (Var): "%" { ((!"'" %operator) / plain_word)* }
+variable (Var): "%" { (plain_word ((!"'" %operator) / plain_word)*)? }
 
 inline_list (List):
     !('[..]')
diff --git a/tests/collections.nom b/tests/collections.nom
index 04b8a78..6329d00 100644
--- a/tests/collections.nom
+++ b/tests/collections.nom
@@ -31,15 +31,15 @@ assume ((values in {x:1}) = [1])
 %x <- [3,1,2]
 sort %x
 assume (%x = [1,2,3])
-sort %x by (-%)
+sort %x by % = (-%)
 assume (%x = [3,2,1])
 %keys <- {1:999,2:0,3:50}
-sort %x by (% in %keys)
+sort %x by % = %keys.%
 assume (%x = [2,3,1])
 assume ((unique [1,2,1,3,2,3]) = [1,2,3])
 %c <- (new counter)
 for % in ["x","y","x","x","y"]
-    (% in %c) +<- 1
+    %c.% +<- 1
 assume (%c = {x:3,y:2})
 
 say "Collections test passed."
diff --git a/tests/math.nom b/tests/math.nom
index 4232d81..8cfd0f4 100644
--- a/tests/math.nom
+++ b/tests/math.nom
@@ -15,5 +15,7 @@ assume
 ..or barf "math functions failed"
 assume ((463 to the nearest 100) = 500) or barf "rounding failed"
 assume ((2.6 to the nearest 0.25) = 2.5) or barf "rounding failed"
+assume ((min of [3,-4,1,2] by % = (%*%)) = 1)
+assume ((max of [3,-4,1,2] by % = (%*%)) = -4)
 
 say "Math test passed"
diff --git a/tests/metaprogramming.nom b/tests/metaprogramming.nom
index 9a4c9b2..26a750a 100644
--- a/tests/metaprogramming.nom
+++ b/tests/metaprogramming.nom
@@ -36,7 +36,20 @@ immediately
     parse [V] as: five
 assume ((V) = 5) or barf "Parse as compile action failed."
 
-remove action "foo %"
+immediately
+    parse [swap %x and %y] as
+        do
+            %tmp <- %x
+            %x <- %y
+            %y <- %tmp
+<- {%1:1, %2:2}
+swap %1 and %2
+assume ((%1 = 2) and (%2 = 1)) or barf "'parse % as %' failed on 'swap % and %'"
+<- {%tmp:1, %tmp2:2}
+swap %tmp and %tmp2
+assume ((%tmp = 2) and (%tmp2 = 1)) or barf "'parse % as %' variable mangling failed."
+
+remove action (foo %)
 try: foo 99
 ..and if it succeeds: barf "Failed to delete action"