Improved error messages, and fixed issue with importing from other modules

analyze_structure.lua

@@ -1,5 +1,10 @@
 
-local TABLE_TYPE = require "table_type"
+local TABLE_TYPE
+do
+    local thispath = ... and select('1', ...):match('.+%.') or ''
+    was_loaded, TABLE_TYPE         =  pcall(require, thispath..'table_type')
+    assert(was_loaded, '[pretty]: Could not load vital library: table_type')
+end
 
 local RESERVED_LUA_WORDS = {
     ['and']      = true,
@@ -147,7 +152,9 @@ function is_short_table (value)
     -- Predicate: value is either an empty table, or one with a single simple
     -- non-function element.
 
-    assert( type(value) == 'table', '[analyze_structure]: Only tables allowed!' )
+    if type(value) ~= 'table' then
+        error(('[pretty/internal]: Only tables allowed in function analyze_structure.is_short_table, but was given %s (%s)'):format(value, type(value)), 2)
+    end
 
     local first_key   = next(value, nil)
     if not first_key then

function.lua

@@ -102,7 +102,6 @@ end
 local function format_function_with_closure (value, options, depth, l, format_value)
 	local info = get_function_info(value)
 
-	--assert(info.nups > 0)
 	local function_str = nil
 	if (info.defined_how == 'string') then
 		function_str = get_full_function_str(info.source, info.linedefined, info.lastlinedefined)

pretty.lua

@@ -13,9 +13,10 @@ do
     -- Load other stuff
     local was_loaded
     was_loaded, analyze_structure  =  pcall(require, thispath..'analyze_structure')
-    assert(was_loaded)
+    print(was_loaded, analyze_structure)
+    assert(was_loaded, '[pretty]: Could not load vital library: analyze_structure')
     was_loaded, TABLE_TYPE         =  pcall(require, thispath..'table_type')
-    assert(was_loaded)
+    assert(was_loaded, '[pretty]: Could not load vital library: table_type')
 end
 --
 
@@ -238,7 +239,9 @@ local SIMPLE_VALUE_TYPES = {
 }
 
 local function is_empty_table (value)
-    assert( type(value) == 'table', '[is_empty_table]: Only tables allowed!' )
+    if type(value) ~= 'table' then
+        error(('[pretty/internal]: Only tables allowed in function pretty.is_empty_table, but was given %s (%s)'):format(value, type(value)), 2)
+    end
     return next(value) == nil
 end
 
@@ -246,7 +249,9 @@ local function is_short_table (value)
     -- In this context, a short table is either an empty table, or one with a
     -- single element.
 
-    assert( type(value) == 'table', '[is_short_table]: Only tables allowed!' )
+    if type(value) ~= 'table' then
+        error(('[pretty/internal]: Only tables allowed in function pretty.is_short_table, but was given %s (%s)'):format(value, type(value)), 2)
+    end
 
     local first_key  = next(value)
     return (not first_key or SIMPLE_VALUE_TYPES[type(value[first_key])])