separate error log from Cache

commands.lua

@@ -997,9 +997,7 @@ function command.reload_all()
     table.insert(column_names, column.name)
   end
   Surface = {}
-  cache_errors = Cache['errors']
   Cache = {}
-  Cache['errors'] = cache_errors
   local old_viewport = {x=Display_settings.x, y=Display_settings.y}
   local old_cursor_pane = Cursor_pane
   Cursor_pane = {col=0,row=1}

errors.lua

@@ -1,7 +1,7 @@
 function add_error(err)
   print(err)
-  table.insert(Cache['errors'].lines, {mode='text', data=err})
-  table.insert(Cache['errors'].line_cache, {})
+  table.insert(Error_log.lines, {mode='text', data=err})
+  table.insert(Error_log.line_cache, {})
   Current_error = err
   Current_error_time = App.getTime()
   Current_error_text = App.newText(love.graphics.getFont(), err)

run.lua

@@ -49,8 +49,6 @@ function run.initialize_globals()
   -- share data between such aliases:
   --   line contents when panes are not editable (editable panes can diverge)
   --   links between files (never in Surface, can never diverge between panes)
-  -- One constraint on Cache: it must always include a properly saved 'errors'
-  -- element (created further down in this function).
   Cache = {}
 
   -- LÖVE renders N frames per second like any game engine, but we don't
@@ -123,8 +121,8 @@ function run.initialize_globals()
   -- blinking cursor
   Cursor_time = 0
 
-  -- errors are not persisted, and stored in Cache['errors']
-  Cache['errors'] = {id='errors', filename=Directory..'errors', left=0, right=Display_settings.column_width, lines={}, line_cache={}}
+  -- a read-only buffer for errors
+  Error_log = {id='errors', filename=Directory..'errors', left=0, right=Display_settings.column_width, lines={}, line_cache={}}
   Current_error = nil
   Current_error_text = nil
   Current_error_time = nil