Made some global Lua variables local

We have to be careful with introducing globals now that there is only a
single Lua state, so we shouldn't use globals unnecessarily. Any variable
should be declared 'local' unless there is a reason to make it global.

For additional safety we can also think about disallowing the use of globals
entirely. This also helps to catch typos in scripts.

Reviewed-by: Erik Schilling

2 files changed, 46 insertions, 47 deletions

diff --git a/example/scripts/crafting.lua b/example/scripts/crafting.lua
index 2200081..db8c76d 100644
--- a/example/scripts/crafting.lua
+++ b/example/scripts/crafting.lua
@@ -4,32 +4,12 @@
 

 --]]

 

--- This function is called by the game engine when a character tries to craft

--- something from items in its inventory

-function on_craft(ch, recipe)

-    -- ch is the crafting character

-    --

-    -- recipe is a table with the ingredients.

-    -- it is a common 1-based array. each element of this array is a table with

-    -- the two keys "id" and "amount".

-    -- The engine has already checked that the character owns enough of those

-    -- things, so you needn't do this again.

-      

-    -- uncomment one (but not both!) of the following three lines to enable the

-    -- example crafting systems

-    

-    mana.chat_message(ch, "There is no crafting in this game world.")

-    --craft_strict(ch, recipe)

-    --craft_lax(ch, recipe)

-end

-

-

 -- a primitive example crafting system which cares about item order and exact amount

-function craft_strict(ch, recipe)

+local function craft_strict(ch, recipe)

     if (recipe[1].id == 8 and recipe[1].amount == 2 and -- has two iron

         recipe[2].id == 9 and recipe[2].amount == 1)    -- and one wood

         then

-        mana.chr_inv_change(ch, 

+        mana.chr_inv_change(ch,

             8, -2, --take away the iron

             9, -1, --take away the wood

             5, 1 ) -- give a sword

@@ -39,38 +19,20 @@ function craft_strict(ch, recipe)
     mana.chat_message(ch, "This wouldn't create anything useful")

 end

 

--- a primitive example crafting system which doesn't care about item order

--- and amount. It even allows to mention the same item multiple times.

-function craft_lax(ch, recipe)

-    recipe = make_condensed_and_sorted_item_list(recipe)

-

-    if (recipe[1].id == 8 and recipe[1].amount >= 2 and -- has at least two iron

-        recipe[2].id == 9 and recipe[2].amount >= 1)    -- and at least one wood

-        then

-        mana.chr_inv_change(ch, 

-            8, -2, -- take away the iron

-            9, -1, -- take away the wood

-            5, 1 ) -- give a sword

-        mana.chat_message(ch, "You've crafted a sword")

-        return

-    end

-    mana.chat_message(ch, "This wouldn't create anything useful")

-end

-

 -- this turns multiple occurences of the same item into one by adding up

 -- their amounts and sorts the recipe by item ID.

 -- This makes stuff a lot easier when your crafting system isn't supposed to

 -- care about the order items are in.

-function make_condensed_and_sorted_item_list(recipe)

+local function make_condensed_and_sorted_item_list(recipe)

     local condensed = {}

-    for index, item in pairs(recipe) do 

+    for index, item in pairs(recipe) do

         if condensed[item.id] == nil then

             condensed[item.id] = item.amount

         else

             condensed[item.id] = condensed[item.id] + item.amount

         end

     end

-    

+

     local sorted = {}

     for id, amount in pairs(condensed) do

         local item = {}

@@ -78,12 +40,49 @@ function make_condensed_and_sorted_item_list(recipe)
         item.amount = amount

         table.insert(sorted, item)

     end

-    

+

     table.sort(sorted, function(item1, item2)

         return (item1.id < item2.id)

     end)

-    

+

     return sorted

 end

 

+-- a primitive example crafting system which doesn't care about item order

+-- and amount. It even allows to mention the same item multiple times.

+local function craft_lax(ch, recipe)

+    recipe = make_condensed_and_sorted_item_list(recipe)

+

+    if (recipe[1].id == 8 and recipe[1].amount >= 2 and -- has at least two iron

+        recipe[2].id == 9 and recipe[2].amount >= 1)    -- and at least one wood

+        then

+        mana.chr_inv_change(ch,

+            8, -2, -- take away the iron

+            9, -1, -- take away the wood

+            5, 1 ) -- give a sword

+        mana.chat_message(ch, "You've crafted a sword")

+        return

+    end

+    mana.chat_message(ch, "This wouldn't create anything useful")

+end

+

+-- This function is registered with the game engine to use when a character

+-- tries to craft something from items in its inventory.

+local function on_craft(ch, recipe)

+    -- ch is the crafting character

+    --

+    -- recipe is a table with the ingredients.

+    -- it is a common 1-based array. each element of this array is a table with

+    -- the two keys "id" and "amount".

+    -- The engine has already checked that the character owns enough of those

+    -- things, so you needn't do this again.

+

+    -- uncomment one (but not both!) of the following three lines to enable the

+    -- example crafting systems

+

+    mana.chat_message(ch, "There is no crafting in this game world.")

+    --craft_strict(ch, recipe)

+    --craft_lax(ch, recipe)

+end

+

 mana.on_craft(on_craft)

diff --git a/example/scripts/special_actions.lua b/example/scripts/special_actions.lua
index 711478f..7e42ad4 100644
--- a/example/scripts/special_actions.lua
+++ b/example/scripts/special_actions.lua
@@ -13,7 +13,7 @@ specialCost[1] = 50
 specialCost[2] = 250
 specialCost[3] = 1000
 
-function use_special(ch, id)
+local function use_special(ch, id)
     -- perform whatever the special with the ID does
     if id == 1 then
         mana.being_say(ch, "Kaaame...Haaame... HAAAAAA!")
@@ -26,7 +26,7 @@ function use_special(ch, id)
     end
 end
 
-function get_special_recharge_cost(id)
+local function get_special_recharge_cost(id)
     -- return the recharge cost for the special with the ID
     return specialCost[id]
 end