very WIP, doesn't detect duplicates properly.. everything else seems fine?

lib/log.lua

@@ -0,0 +1,75 @@
+local stored_messages = {}
+local display_levels = {}
+local enable_logging = true
+local message_limit = math.huge
+
+-- USAGE:
+--   -- set arbitrary log levels to be printed immediately
+--   log{ info = true, warning = true, ducksauce = true, }
+--   -- send anything (except nil) to a log level
+--   log("bacom", true, "text", 5, function() end, {})
+--   -- print all messages saved at a particular log level
+--   log("error")
+--   -- toggle ALL logging on and off with a boolean
+--   log(false) -- this deletes all stored messages
+--   -- set a maximum number of stored messages per log level
+--   log(50) -- warning: reaching large limits makes logging expensive
+--   -- do anything to the stored messages (this example deletes them all)
+--  log(function(messages) return {} end)
+
+return function(options, ...)
+  local options_type = type(options)
+
+  if (options_type == "string") and enable_logging then
+    if not stored_messages[options] then stored_messages[options] = {} end
+    local message_table = stored_messages[options]
+
+    -- turn log message into text
+    local tab = {...}
+    for i = 1, #tab do
+      tab[i] = tostring(tab[i])
+    end
+    local current_message = table.concat(tab, "\t")
+
+    if #current_message == 0 then
+      -- print all stored_messages of specified level
+      for i = 1, #message_table do
+        print(message_table[i])
+      end
+
+    else
+      -- store message (and print if in display_levels)
+      message_table[#message_table + 1] = current_message
+      if #message_table > message_limit then table.remove(message_table, 1) end
+      if display_levels[options] then print(current_message) end
+    end
+
+  -- set display_levels
+  elseif options_type == "table" then
+    for k,v in pairs(options) do
+      display_levels[k] = v
+    end
+
+  elseif options_type == "number" then
+    message_limit = options
+    for k,v in pairs(stored_messages) do
+      while #v > message_limit do
+        table.remove(v, 1)
+      end
+    end
+
+  -- turn all logging off and delete stored messages; or turn it on
+  elseif options_type == "boolean" then
+    if options then
+      enable_logging = true
+    else
+      enable_logging = false
+      stored_messages = {}
+    end
+
+  -- arbitrary access :D
+  elseif options_type == "function" then
+    local result = options(stored_messages)
+    if type(result) == "table" then stored_messages = result end
+  end
+end

lib/timing.lua

@@ -40,6 +40,7 @@ timing.mark = function(label)
   if #timing > 1 then
     timing.display(#timing)
   end
+  print("", "", label)
 end
 
 timing.estimate = function(current_position, total_operations)

lib/utility.lua

@@ -221,7 +221,7 @@ utility.list = function(path, func)
 
   local run = function(fn)
     for line in output:gmatch("[^\r\n]+") do -- thanks to https://stackoverflow.com/a/32847589
-      if not (line == "." or line == "..") then
+      if not ((line == ".") or (line == "..")) then
         fn(line)
       end
     end
@@ -239,7 +239,8 @@ utility.ls = function(...)
   return utility.list(...)
 end
 
-utility.tree = function(path, options, fn)
+local tree
+tree = function(path, options, fn)
   if type(options) == "function" then
     fn = options
     options = {}
@@ -258,7 +259,16 @@ utility.tree = function(path, options, fn)
 
       fn(path_name)
     else
-      utility.tree(path .. utility.path_separator .. path_name, options, fn)
+      tree(path .. utility.path_separator .. path_name, options, fn)
+    end
+  end)
+end
+utility.tree = function(path, options, fn)
+  tree(path, options, function(path_name)
+    if path_name:find(path) == 1 then
+      fn(path_name)
+    else
+      fn(path .. utility.path_separator .. path_name)
     end
   end)
 end