From 453cae7362ab31be5b1b50a15e5aa5fd2c5fd654 Mon Sep 17 00:00:00 2001
From: Jason Perkins <starkos@industriousone.com>
Date: Wed, 20 Feb 2013 09:45:35 -0500
Subject: [PATCH] Add table.foreachi(), phase out ipairs() in API so nil values
 can be included in lists

---
 src/base/api.lua   | 26 ++++++++++----------
 src/base/table.lua | 59 +++++++++++++++++++++++++++++++++-------------
 2 files changed, 56 insertions(+), 29 deletions(-)

diff --git a/src/base/api.lua b/src/base/api.lua
index f36bf0fe..030a68e7 100644
--- a/src/base/api.lua
+++ b/src/base/api.lua
@@ -140,9 +140,9 @@
 
 		function recurse(value)
 			if type(value) == "table" then
-				for _, v in ipairs(value) do
+				table.foreachi(value, function(v)
 					recurse(v)
-				end
+				end)
 			else
 				remover(removes, value)
 			end
@@ -182,7 +182,9 @@
 			if type(field.allowed) == "function" then
 				return field.allowed(value)
 			else
-				for _,v in ipairs(field.allowed) do
+				local n = #field.allowed
+				for i = 1, n do
+					local v = field.allowed[i]
 					if value:lower() == v:lower() then
 						return v
 					end
@@ -341,10 +343,10 @@
 	function api.setfile(target, name, field, value)
 		if value:find("*") then
 			local values = os.matchfiles(value)
-			for _, value in ipairs(values) do
-				api.setfile(target, name, field, value)
+			table.foreachi(values, function(v)
+				api.setfile(target, name, field, v)
 				name = name + 1
-			end
+			end)
 		else
 			target[name] = path.getabsolute(value)
 		end
@@ -353,10 +355,10 @@
 	function api.setdirectory(target, name, field, value)
 		if value:find("*") then
 			local values = os.matchdirs(value)
-			for _, value in ipairs(values) do
-				api.setdirectory(target, name, field, value)
+			table.foreachi(values, function(v)
+				api.setdirectory(target, name, field, values[i])
 				name = name + 1
-			end
+			end)
 		else
 			target[name] = path.getabsolute(value)
 		end
@@ -411,9 +413,9 @@
 		local result = {}
 		function recurse(value)
 			if type(value) == "table" then
-				for _, v in ipairs(value) do
-					recurse(v)
-				end
+				table.foreachi(value, function (value)
+					recurse(value)
+				end)
 			else
 				setter(result, #result + 1, field, value)
 			end
diff --git a/src/base/table.lua b/src/base/table.lua
index 849a787b..9bea0932 100644
--- a/src/base/table.lua
+++ b/src/base/table.lua
@@ -3,7 +3,7 @@
 -- Additions to Lua's built-in table functions.
 -- Copyright (c) 2002-2008 Jason Perkins and the Premake project
 --
-	
+
 
 --
 -- Returns true if the table contains the specified value.
@@ -17,7 +17,7 @@
 		end
 		return false
 	end
-	
+
 
 --
 -- Make a copy of the indexed elements of the table.
@@ -39,23 +39,23 @@
 	function table.deepcopy(object)
 		-- keep track of already seen objects to avoid loops
 		local seen = {}
-		
+
 		local function copy(object)
 			if type(object) ~= "table" then
 				return object
 			elseif seen[object] then
 				return seen[object]
 			end
-			
+
 			local clone = {}
 			seen[object] = clone
 			for key, value in pairs(object) do
 				clone[key] = copy(value)
 			end
-			
+
 			return clone
 		end
-		
+
 		return copy(object)
 	end
 
@@ -72,8 +72,8 @@
 		end
 		return result
 	end
-	
-	
+
+
 
 --
 -- Flattens a hierarchy of tables into a single array containing all
@@ -81,23 +81,48 @@
 --
 
 	function table.flatten(arr)
-		local result = { }
-		
+		local result = {}
+
 		local function flatten(arr)
-			for _, v in ipairs(arr) do
+			local n = #arr
+			for i = 1, n do
+				local v = arr[i]
 				if type(v) == "table" then
 					flatten(v)
-				else
+				elseif v then
 					table.insert(result, v)
 				end
 			end
 		end
-		
+
 		flatten(arr)
 		return result
 	end
 
 
+--
+-- Walk the elements of an array and call the specified function
+-- for each non-nil element. This works around a "feature" of the
+-- ipairs() function that stops iteration at the first nil.
+--
+-- @param arr
+--    The array to iterate.
+-- @param func
+--    The function to call. The value (not the index) will be passed
+--    as the only argument.
+--
+
+	function table.foreachi(arr, func)
+		local n = #arr
+		for i = 1, n do
+			local v = arr[i]
+			if v then
+				func(v)
+			end
+		end
+	end
+
+
 --
 -- Merge two lists into an array of objects, containing pairs
 -- of values, one from each list.
@@ -136,7 +161,7 @@
 
 --
 -- Inserts a value of array of values into a table. If the value is
--- itself a table, its contents are enumerated and added instead. So 
+-- itself a table, its contents are enumerated and added instead. So
 -- these inputs give these outputs:
 --
 --   "x" -> { "x" }
@@ -229,7 +254,7 @@
 			if tbl[i] == obj then
 				return i
 			end
-		end		
+		end
 	end
 
 
@@ -253,5 +278,5 @@
 		end
 		return result
 	end
-	
-		
+
+