Fixes and improvements, and ported nomsu.3.peg to new tidier syntax.

8 files changed, 168 insertions, 319 deletions

diff --git a/nomsu.3.peg b/nomsu.3.peg
index 244a621..21fa86c 100644
--- a/nomsu.3.peg
+++ b/nomsu.3.peg
@@ -3,69 +3,94 @@ file:
     {:curr_indent: ' '* :}
     (((action / expression / inline_block / indented_block) eol !.)
      / file_chunks / empty_block)
-    %ws* (!! .+ -> "Parse error" !!)?
+    {:curr_indent: %nil :}
+    !.
 
-shebang: "#!" (!"nomsu" [^%nl])* "nomsu" %ws+ "-V" %ws* {:version: [0-9.]+ :} [^%nl]*
+shebang: "#!" (!"nomsu" [^%nl])* "nomsu" ws+ "-V" ws* {:version: [0-9.]+ :} [^%nl]*
 
 file_chunks (FileChunks):
     {:curr_indent: ' '* :}
     shebang? comment? blank_lines?
     (top_block (nl_nodent section_division top_block)*)
     blank_lines?
+    ws* unexpected_chunk?
+    {:curr_indent: %nil :}
 
 top_block (Block):
     {:curr_indent: ' '* :}
     comment? blank_lines? statement (nl_nodent statement)*
+    {:curr_indent: %nil :}
 
 empty_block (Block):
     {:curr_indent: ' '* :}
     comment? blank_lines?
+    {:curr_indent: %nil :}
 
-nodent: =curr_indent !(" ")
+nodent: (unexpected_indent [^%nl]* / =curr_indent)
 indent: =curr_indent "    "
-blank_lines: %nl ((nodent comment / %ws*) %nl)*
-eol: %ws* eol_comment? (!. / &%nl)
+blank_lines: %nl ((nodent comment / ws*) %nl)*
+eol: ws* eol_comment? (!. / &%nl)
 
 nl_nodent: blank_lines nodent
-nl_indent: blank_lines {:curr_indent: indent :} (comment nl_nodent)?
-
-comment:
-    "#" (({} {~ [^%nl]* (%nl+ (indent -> '') [^%nl]*)* ~} %userdata) => add_comment)
-eol_comment:
-    "#" (({} {[^%nl]*} %userdata) => add_comment)
+nl_indent: blank_lines {:curr_indent: indent :} (comment nl_nodent)*
+
+comment (Comment):
+    "#" {~ [^%nl]* (%nl+ (indent -> '') [^%nl]*)* ~}
+eol_comment (Comment):
+    "#" {[^%nl]*}
+
+unexpected_code: ws* _unexpected_code
+_unexpected_code (Error):
+    {:error: {~ [^%nl]+ -> "Couldn't parse this code" ~} :}
+unexpected_chunk (Error):
+    {:error: {~ .+ -> "Couldn't parse this code" ~} :}
+unexpected_indent (Error):
+    {:error: {~ (=curr_indent ws+) -> "Messed up indentation" ~} :}
+    {:hint: {~ '' -> 'Either make sure this line is aligned with the one above it, or make sure the previous line ends with something that uses indentation, like ":" or "(..)"' ~} :}
+missing_paren_err (Error):
+    {:error: {~ eol -> 'Line ended without finding a closing )-parenthesis' ~} :}
+    {:hint: {~ '' -> 'Put a ")" here' ~} :}
+missing_quote_err (Error):
+    {:error: {~ eol -> 'Line ended before finding a closing double quotation mark' ~} :}
+    {:hint: {~ "" -> "Put a quotation mark here" ~} :}
+missing_bracket_error (Error):
+    {:error: {~ eol -> "Line ended before finding a closing ]-bracket" ~} :}
+    {:hint: {~ '' -> 'Put a "]" here' ~} :}
+missing_brace_error (Error):
+    {:error: {~ eol -> "Line ended before finding a closing }-brace" ~} :}
+    {:hint: {~ '' -> 'Put a "}" here' ~} :}
 
 section_division: ("~")^+3 eol
 
 inline_block:
-    "(" %ws* inline_block  %ws* ")" / raw_inline_block
+    "(" ws* inline_block  ws* ")" / raw_inline_block
 raw_inline_block (Block):
-    (!"::") ":" %ws* ((inline_statement (%ws* ";" %ws* inline_statement)*) / !(eol nl_indent))
+    (!"::") ":" ws* ((inline_statement (ws* ";" ws* inline_statement)*) / !(eol nl_indent))
 indented_block (Block):
-    ":" eol nl_indent statement (nl_nodent statement)* (%nl (%ws* %nl)* nodent comment)*
+    ":" eol nl_indent statement (nl_nodent statement)*
+    (%nl (ws* %nl)* nodent (comment / eol / unexpected_code))*
+    {:curr_indent: %nil :}
 
 statement:
-    (action / expression) (eol / (!! [^%nl]+ -> "Unexpected code while parsing line" !!))
+    (action / expression) (eol / unexpected_code)
 
 inline_statement: (inline_action / inline_expression)
 
 noindex_inline_expression:
     number / variable / inline_text / inline_list / inline_dict / inline_nomsu
     / ( "("
-            %ws* (inline_action / inline_expression) %ws*
-            (%ws* ',' %ws* (inline_action / inline_expression) %ws*)*
-        (")"
-            / (!! eol -> 'Line ended without finding a closing )-parenthesis' !!)
-            / (!! [^%nl]+ -> 'Unexpected code while parsing subexpression' !!)
-        )
+            ws* (inline_action / inline_expression) ws*
+            (ws* ',' ws* (inline_action / inline_expression) ws*)*
+        (")" / missing_paren_err / unexpected_code)
       )
 inline_expression: index_chain / noindex_inline_expression 
 indented_expression:
     indented_text / indented_nomsu / indented_list / indented_dict / ({|
         "(..)" nl_indent
-            (action / expression) (nl_nodent comment)*
-            (eol / (!! [^%nl]+ -> "Unexpected code while parsing indented expression" !!))
+            (action / expression) (eol / unexpected_code)
+            (%nl (ws* %nl)* nodent (comment / eol / unexpected_code))*
+        {:curr_indent: %nil :}
     |} -> unpack)
-    / (nl_indent (!! [^%nl]* -> "Unexpected indentation. Perhaps you meant to put a ':' or '(..)' on the previous line?" !!) (nl_nodent [^%nl]*)*)
 expression:
     inline_expression / indented_expression
 
@@ -79,45 +104,42 @@ index_chain (IndexChain):
 -- Actions need either at least 1 word, or at least 2 tokens
 inline_action (Action):
     !section_division
-    ({:target: inline_arg :} %ws* "::" %ws*)?
-    (   (inline_arg (%ws* (inline_arg / word))+)
-      / (word       (%ws* (inline_arg / word))*))
-    (%ws* inline_block)?
+    ({:target: inline_arg :} ws* "::" ws*)?
+    (   (inline_arg (ws* (inline_arg / word))+)
+      / (word       (ws* (inline_arg / word))*))
+    (ws* inline_block)?
 inline_arg: inline_expression / inline_block
 action (Action):
     !section_division
-    ({:target: arg :} (nl_nodent "..")? %ws* "::" (nl_nodent "..")? %ws*)?
-    (  (arg  ((nl_nodent "..")? %ws* (arg / word))+)
-     / (word ((nl_nodent "..")? %ws* (arg / word))*))
+    ({:target: arg :} (nl_nodent "..")? ws* "::" (nl_nodent "..")? ws*)?
+    (  (arg  ((nl_nodent "..")? ws* (arg / word))+)
+     / (word ((nl_nodent "..")? ws* (arg / word))*))
 arg: expression / inline_block / indented_block
 
-word: !number { %operator_char+ / %ident_char+ }
+word: !number { operator_char+ / ident_char+ }
 
 text_word (Text): word
 
 inline_text (Text):
-    !('".."' eol)
-    '"'
-        ({~ (('\"' -> '"') / ('\\' -> '\') / %escaped_char / [^%nl\"])+ ~}
-        / inline_text_interpolation)*
-    ('"'
-     / (!! eol -> 'Line ended before finding a closing double quotation mark' !!)
-     / (!! [^%nl]+ -> 'Unexpected code while parsing Text' !!))
+    !(indented_text)
+    ('"' _inline_text* ('"' / missing_quote_err / unexpected_code))
+_inline_text:
+    {~ (('\"' -> '"') / ('\\' -> '\') / escaped_char / [^%nl\"]+)+ ~}
+    / inline_text_interpolation
 inline_text_interpolation:
     "\" (
         variable / inline_list / inline_dict / inline_text
         / ("("
-            %ws* (inline_action / inline_expression) %ws*
-            (%ws* ',' %ws* (inline_action / inline_expression) %ws*)*
-        (")"
-         / (!! eol -> 'Line ended without finding a closing )-parenthesis' !!)
-         / (!! [^%nl]+ -> 'Unexpected code while parsing Text interpolation' !!)))
+            ws* (inline_action / inline_expression) ws*
+            (ws* ',' ws* (inline_action / inline_expression) ws*)*
+        (")" / missing_paren_err / unexpected_code))
     )
 
 indented_text (Text):
-    '".."' eol %nl {%nl*} {:curr_indent: indent :}
+    '".."' eol %nl {%nl+}? {:curr_indent: indent :}
         (indented_plain_text / text_interpolation / {~ %nl+ (=curr_indent -> "") ~})*
-    (!! [^%nl]+ -> "Unexpected code while parsing Text" !!)?
+    unexpected_code?
+    {:curr_indent: %nil :}
 -- Tracking text-lines-within-indented-text as separate objects allows for better debugging line info
 indented_plain_text (Text):
     {~ (("\\" -> "\") / (("\" blank_lines =curr_indent "..") -> "") / (!text_interpolation "\") / [^%nl\]+)+
@@ -129,43 +151,51 @@ number (Number): (("-"? (([0-9]+ "." [0-9]+) / ("." [0-9]+) / "0x" [0-9a-fA-F]+
 
 -- Variables can be nameless (i.e. just %) and can only contain identifier chars.
 -- This ensures you don't get weird parsings of `%x+%y` or `%'s thing`.
-variable (Var): "%" {%ident_char*}
+variable (Var): "%" {ident_char*}
 
 inline_list (List):
     !('[..]')
-    "[" %ws*
-        (inline_list_item (%ws* ',' %ws* inline_list_item)* (%ws* ',')?)? %ws*
-    ("]" / (","? (
-        (!! eol -> "Line ended before finding a closing ]-bracket" !!)
-       /(!! [^%nl]+ -> "Unexpected code while parsing List" !!)
-    )))
+    "[" ws*
+        (inline_list_item (ws* ',' ws* inline_list_item)* (ws* ',')?)? ws*
+    ("]" / (","? (missing_bracket_error / unexpected_code)))
 indented_list (List):
     "[..]" eol nl_indent
-        list_line (nl_nodent list_line)* (nl_nodent comment)*
-    (","? (!! [^%nl]+ -> "Unexpected code while parsing List" !!))?
+        list_line (nl_nodent list_line)*
+        (%nl (ws* %nl)* nodent (comment / eol / unexpected_code))*
+    (","? unexpected_code)?
 list_line:
-      (inline_list_item %ws* "," %ws*)+ eol
-    / (inline_list_item %ws* "," %ws*)* (action / expression) eol
+      (inline_list_item ws* "," ws*)+ eol
+    / (inline_list_item ws* "," ws*)* (action / expression) eol
 inline_list_item: inline_action / inline_expression
 
 inline_dict (Dict):
     !('{..}')
-    "{" %ws*
-        (inline_dict_entry (%ws* ',' %ws* inline_dict_entry)*)? %ws*
-    ("}" / (","? (
-        (!! eol -> "Line ended before finding a closing }-brace" !!)
-      / (!! [^%nl]* -> "Unexpected code while parsing Dictionary" !!)
-    )))
+    "{" ws*
+        (inline_dict_entry (ws* ',' ws* inline_dict_entry)*)? ws*
+    ("}" / (","? (missing_brace_error / unexpected_code)))
 indented_dict (Dict):
     "{..}" eol nl_indent
-        dict_line (nl_nodent dict_line)* (nl_nodent comment)*
-    (","? (!! [^%nl]+ -> "Unexpected code while parsing Dictionary" !!))?
+        dict_line (nl_nodent dict_line)*
+        (%nl (ws* %nl)* nodent (comment / eol / unexpected_code))*
+    (","? unexpected_code)?
 dict_line:
-      (inline_dict_entry %ws* "," %ws*)+ eol
-    / (inline_dict_entry %ws* "," %ws*)* dict_entry eol
+      (inline_dict_entry ws* "," ws*)+ eol
+    / (inline_dict_entry ws* "," ws*)* dict_entry eol
 dict_entry(DictEntry):
-    dict_key (%ws* ":" %ws* (action / expression))?
+    dict_key (ws* ":" ws* (action / expression))?
 inline_dict_entry(DictEntry):
-    dict_key (%ws* ":" %ws* (inline_action / inline_expression)?)?
+    dict_key (ws* ":" ws* (inline_action / inline_expression)?)?
 dict_key:
     text_word / inline_expression
+
+operator_char: ['`~!@$^&*+=|<>?/-]
+ident_char: [a-zA-Z0-9_] / %utf8_char
+ws: [ %tab]
+
+escaped_char:
+    ("\"->'') (
+        (([xX]->'') ((({[0-9a-fA-F]^2} %number_16) -> tonumber) -> tochar))
+      / ((([0-9] [0-9]^-2) -> tonumber) -> tochar)
+      / ("a"->ascii_7)  / ("b"->ascii_8)  / ("t"->ascii_9)  / ("n"->ascii_10)
+      / ("v"->ascii_11) / ("f"->ascii_12) / ("r"->ascii_13)
+    )
diff --git a/nomsu.4.peg b/nomsu.4.peg
index eb0c878..8d8296e 100644
--- a/nomsu.4.peg
+++ b/nomsu.4.peg
@@ -11,14 +11,14 @@ shebang: "#!" (!"nomsu" [^%nl])* "nomsu" ws+ "-V" ws* {:version: [0-9.]+ :} [^%n
 file_chunks (FileChunks):
     {:curr_indent: ' '* :}
     shebang? comment? blank_lines?
-    (top_block (section_division nl_nodent top_block)*)
+    (top_block (nl_nodent section_division top_block)*)
     blank_lines?
     ws* unexpected_chunk?
     {:curr_indent: %nil :}
 
 top_block (Block):
     {:curr_indent: ' '* :}
-    comment? blank_lines? statement (nl_nodent statement?)*
+    comment? blank_lines? statement (nl_nodent statement)*
     {:curr_indent: %nil :}
 
 empty_block (Block):
@@ -71,7 +71,7 @@ inline_block:
 raw_inline_block (Block):
     (!"::") ":" ws* ((inline_statement (ws* ";" ws* inline_statement)*) / !(eol nl_indent))
 indented_block (Block):
-    ":" eol nl_indent statement (nl_nodent statement?)*
+    ":" eol nl_indent statement (nl_nodent statement)*
     (%nl (ws* %nl)* nodent (comment / eol / unexpected_code))*
     {:curr_indent: %nil :}
 
@@ -149,19 +149,16 @@ indented_text (Text):
 cool_quote:
     '"' !(%nl+ !(=curr_indent))
 cool_indented_text (Text):
-    ({|
-        '"'
-        _inline_text* 
-        (('\' %nl+ {:curr_indent: indent :} '..')
-         / disallowed_interpolation? {%nl+} {:curr_indent: indent :})
-        (indented_cool_plain_text / text_interpolation / {~ %nl+ (=curr_indent -> "") ~})*
-        ('"' eol / missing_quote_err)
-    |} -> unpack)
+    '"'
+    _inline_text* 
+    (('\' %nl+ {:curr_indent: indent :} '..')
+     / disallowed_interpolation? {%nl+} {:curr_indent: indent :})
+    (indented_cool_plain_text / text_interpolation / {~ %nl+ (=curr_indent -> "") ~})*
+    ('"' eol / missing_quote_err)
 indented_cool_plain_text (Text):
     {~ ((("\" blank_lines =curr_indent "..") -> "") / (!text_interpolation ((!("\n") escaped_char) / ('\\' -> '\') / '\')) / (cool_quote / [^%nl"\])+)+
         (%nl+ (=curr_indent -> ""))* ~}
 
-
 -- Tracking text-lines-within-indented-text as separate objects allows for better debugging line info
 indented_plain_text (Text):
     {~ (("\\" -> "\") / (("\" blank_lines =curr_indent "..") -> "") / (!text_interpolation "\") / [^%nl\]+)+
@@ -182,7 +179,7 @@ inline_list (List):
     ("]" / (","? (missing_bracket_error / unexpected_code)))
 indented_list (List):
     "[..]" eol nl_indent
-        list_line (nl_nodent list_line?)*
+        list_line (nl_nodent list_line)*
         (%nl (ws* %nl)* nodent (comment / eol / unexpected_code))*
     (","? unexpected_code)?
 list_line:
@@ -197,7 +194,7 @@ inline_dict (Dict):
     ("}" / (","? (missing_brace_error / unexpected_code)))
 indented_dict (Dict):
     "{..}" eol nl_indent
-        dict_line (nl_nodent dict_line?)*
+        dict_line (nl_nodent dict_line)*
         (%nl (ws* %nl)* nodent (comment / eol / unexpected_code))*
     (","? unexpected_code)?
 dict_line:
diff --git a/nomsu_compiler.lua b/nomsu_compiler.lua
index 510de16..5578e0e 100644
--- a/nomsu_compiler.lua
+++ b/nomsu_compiler.lua
@@ -62,12 +62,45 @@ table.copy = function(t)
     return _tbl_0
   end)(), getmetatable(t))
 end
+local make_tree
+make_tree = function(tree, userdata)
+  local cls = AST[tree.type]
+  tree.source = Source(userdata.filename, tree.start, tree.stop)
+  tree.start, tree.stop = nil, nil
+  tree.type = nil
+  do
+    local _accum_0 = { }
+    local _len_0 = 1
+    for _index_0 = 1, #tree do
+      local t = tree[_index_0]
+      if AST.is_syntax_tree(t, "Comment") then
+        _accum_0[_len_0] = t
+        _len_0 = _len_0 + 1
+      end
+    end
+    tree.comments = _accum_0
+  end
+  if #tree.comments == 0 then
+    tree.comments = nil
+  end
+  for i = #tree, 1, -1 do
+    if AST.is_syntax_tree(tree[i], "Comment") then
+      table.remove(tree, i)
+    end
+  end
+  tree = setmetatable(tree, cls)
+  cls.source_code_for_tree[tree] = userdata.source
+  if tree.__init then
+    tree:__init()
+  end
+  return tree
+end
 local Parsers = { }
 local max_parser_version = 0
 for version = 1, 999 do
   local _continue_0 = false
   repeat
-    if not (version == 4) then
+    if not (version == 4 or version == 3) then
       _continue_0 = true
       break
     end
@@ -84,40 +117,8 @@ for version = 1, 999 do
       break
     end
     max_parser_version = version
-    local make_tree
-    make_tree = function(tree, userdata)
-      local cls = AST[tree.type]
-      tree.source = Source(userdata.filename, tree.start, tree.stop)
-      tree.start, tree.stop = nil, nil
-      tree.type = nil
-      do
-        local _accum_0 = { }
-        local _len_0 = 1
-        for _index_0 = 1, #tree do
-          local t = tree[_index_0]
-          if AST.is_syntax_tree(t, "Comment") then
-            _accum_0[_len_0] = t
-            _len_0 = _len_0 + 1
-          end
-        end
-        tree.comments = _accum_0
-      end
-      if #tree.comments == 0 then
-        tree.comments = nil
-      end
-      for i = #tree, 1, -1 do
-        if AST.is_syntax_tree(tree[i], "Comment") then
-          table.remove(tree, i)
-        end
-      end
-      tree = setmetatable(tree, cls)
-      cls.source_code_for_tree[tree] = userdata.source
-      if tree.__init then
-        tree:__init()
-      end
-      return tree
-    end
-    Parsers[version] = make_parser(peg_file:read("*a"), make_tree)
+    local peg_contents = peg_file:read("*a")
+    Parsers[version] = make_parser(peg_contents, make_tree)
     peg_file:close()
     _continue_0 = true
   until true
diff --git a/nomsu_compiler.moon b/nomsu_compiler.moon
index 4300327..606bf45 100644
--- a/nomsu_compiler.moon
+++ b/nomsu_compiler.moon
@@ -38,10 +38,25 @@ table.copy = (t)-> setmetatable({k,v for k,v in pairs(t)}, getmetatable(t))
 -- consider non-linear codegen, rather than doing thunks for things like comprehensions
 -- Re-implement nomsu-to-lua comment translation?
 
+make_tree = (tree, userdata)->
+    cls = AST[tree.type]
+    tree.source = Source(userdata.filename, tree.start, tree.stop)
+    tree.start, tree.stop = nil, nil
+    tree.type = nil
+    tree.comments = [t for t in *tree when AST.is_syntax_tree(t, "Comment")]
+    if #tree.comments == 0 then tree.comments = nil
+    for i=#tree,1,-1
+        if AST.is_syntax_tree(tree[i], "Comment")
+            table.remove(tree, i)
+    tree = setmetatable(tree, cls)
+    cls.source_code_for_tree[tree] = userdata.source
+    if tree.__init then tree\__init!
+    return tree
+
 Parsers = {}
 max_parser_version = 0
 for version=1,999
-    continue unless version == 4 -- TODO: remove
+    continue unless version == 4 or version == 3 -- TODO: remove
     peg_file = io.open("nomsu.#{version}.peg")
     if not peg_file and package.nomsupath
         for path in package.nomsupath\gmatch("[^;]+")
@@ -49,21 +64,8 @@ for version=1,999
             break if peg_file
     break unless peg_file
     max_parser_version = version
-    make_tree = (tree, userdata)->
-        cls = AST[tree.type]
-        tree.source = Source(userdata.filename, tree.start, tree.stop)
-        tree.start, tree.stop = nil, nil
-        tree.type = nil
-        tree.comments = [t for t in *tree when AST.is_syntax_tree(t, "Comment")]
-        if #tree.comments == 0 then tree.comments = nil
-        for i=#tree,1,-1
-            if AST.is_syntax_tree(tree[i], "Comment")
-                table.remove(tree, i)
-        tree = setmetatable(tree, cls)
-        cls.source_code_for_tree[tree] = userdata.source
-        if tree.__init then tree\__init!
-        return tree
-    Parsers[version] = make_parser(peg_file\read("*a"), make_tree)
+    peg_contents = peg_file\read("*a")
+    Parsers[version] = make_parser(peg_contents, make_tree)
     peg_file\close!
 
 MAX_LINE = 80 -- For beautification purposes, try not to make lines much longer than this value
diff --git a/parser.lua b/parser.lua
index 8a94314..5eed3be 100644
--- a/parser.lua
+++ b/parser.lua
@@ -113,126 +113,9 @@ setmetatable(NOMSU_DEFS, {
   end
 })
 local Parser = {
-  version = 3,
+  version = 4,
   patterns = { }
 }
-do
-  local peg_tidier = re.compile([[    file <- %nl* {~ (def/comment) (%nl+ (def/comment))* %nl* ~}
-    def <- anon_def / captured_def
-    anon_def <- ({ident} (" "*) ":"
-        {~ ((%nl " "+ def_line?)+) / def_line ~}) -> "%1 <- %2"
-    captured_def <- ({ident} (" "*) "(" {ident} ")" (" "*) ":"
-        {~ ((%nl " "+ def_line?)+) / def_line ~}) -> "%1 <- (({} {| %3 |} {} %%userdata) -> %2)"
-    def_line <- (err / [^%nl])+
-    err <- ("(!!" { (!("!!)") .)* } "!!)") -> "(({} (%1) %%userdata) => error)"
-    ident <- [a-zA-Z_][a-zA-Z0-9_]*
-    comment <- "--" [^%nl]*
-    ]])
-  for version = 1, Parser.version do
-    local peg_file = io.open("nomsu." .. tostring(version) .. ".peg")
-    if not peg_file and package.nomsupath then
-      for path in package.nomsupath:gmatch("[^;]+") do
-        peg_file = io.open(path .. "/nomsu." .. tostring(version) .. ".peg")
-        if peg_file then
-          break
-        end
-      end
-    end
-    assert(peg_file, "could not find nomsu .peg file")
-    local nomsu_peg = peg_tidier:match(peg_file:read('*a'))
-    peg_file:close()
-    Parser.patterns[version] = re.compile(nomsu_peg, NOMSU_DEFS)
-  end
-end
-local _anon_chunk = 0
-Parser.parse = function(nomsu_code, source, version)
-  if source == nil then
-    source = nil
-  end
-  if version == nil then
-    version = nil
-  end
-  source = source or nomsu_code.source
-  nomsu_code = tostring(nomsu_code)
-  if not (source) then
-    source = Source("anonymous chunk #" .. tostring(_anon_chunk), 1, #nomsu_code)
-    _anon_chunk = _anon_chunk + 1
-  end
-  version = version or nomsu_code:match("^#![^\n]*nomsu[ ]+-V[ ]*([0-9.]+)")
-  local syntax_version = version and tonumber(version:match("^[0-9]+")) or Parser.version
-  local userdata = {
-    errors = { },
-    source = source,
-    comments = { }
-  }
-  local tree = Parser.patterns[syntax_version]:match(nomsu_code, nil, userdata)
-  if not tree or type(tree) == 'number' then
-    error("In file " .. tostring(colored.blue(tostring(source or "<unknown>"))) .. " failed to parse:\n" .. tostring(colored.onyellow(colored.black(nomsu_code))))
-  end
-  if next(userdata.errors) then
-    local keys
-    do
-      local _accum_0 = { }
-      local _len_0 = 1
-      for k, v in pairs(userdata.errors) do
-        _accum_0[_len_0] = k
-        _len_0 = _len_0 + 1
-      end
-      keys = _accum_0
-    end
-    table.sort(keys)
-    local errors
-    do
-      local _accum_0 = { }
-      local _len_0 = 1
-      for _index_0 = 1, #keys do
-        local k = keys[_index_0]
-        _accum_0[_len_0] = userdata.errors[k]
-        _len_0 = _len_0 + 1
-      end
-      errors = _accum_0
-    end
-    error("Errors occurred while parsing (v" .. tostring(syntax_version) .. "):\n\n" .. table.concat(errors, "\n\n"), 0)
-  end
-  local comments
-  do
-    local _accum_0 = { }
-    local _len_0 = 1
-    for p, c in pairs(userdata.comments) do
-      _accum_0[_len_0] = {
-        comment = c,
-        pos = p
-      }
-      _len_0 = _len_0 + 1
-    end
-    comments = _accum_0
-  end
-  table.sort(comments, function(a, b)
-    return a.pos > b.pos
-  end)
-  local comment_i = 1
-  local walk_tree
-  walk_tree = function(t)
-    local comment_buff = { }
-    while comments[#comments] and comments[#comments].pos <= t.source.start do
-      table.insert(comment_buff, table.remove(comments))
-    end
-    for _index_0 = 1, #t do
-      local x = t[_index_0]
-      if AST.is_syntax_tree(x) then
-        walk_tree(x)
-      end
-    end
-    while comments[#comments] and comments[#comments].pos <= t.source.stop do
-      table.insert(comment_buff, table.remove(comments))
-    end
-    if #comment_buff > 0 then
-      t.comments = comment_buff
-    end
-  end
-  walk_tree(tree)
-  return tree
-end
 Parser.is_operator = function(s)
   return not not (NOMSU_DEFS.operator_char ^ 1 * -1):match(s)
 end
diff --git a/parser.moon b/parser.moon
index f2e5b17..2adfe1b 100644
--- a/parser.moon
+++ b/parser.moon
@@ -74,73 +74,7 @@ setmetatable(NOMSU_DEFS, {__index:(key)=>
     return make_node
 })
 
-Parser = {version:3, patterns:{}}
-do
-    -- Just for cleanliness, I put the language spec in its own file using a slightly modified
-    -- version of the lpeg.re syntax.
-    peg_tidier = re.compile [[
-    file <- %nl* {~ (def/comment) (%nl+ (def/comment))* %nl* ~}
-    def <- anon_def / captured_def
-    anon_def <- ({ident} (" "*) ":"
-        {~ ((%nl " "+ def_line?)+) / def_line ~}) -> "%1 <- %2"
-    captured_def <- ({ident} (" "*) "(" {ident} ")" (" "*) ":"
-        {~ ((%nl " "+ def_line?)+) / def_line ~}) -> "%1 <- (({} {| %3 |} {} %%userdata) -> %2)"
-    def_line <- (err / [^%nl])+
-    err <- ("(!!" { (!("!!)") .)* } "!!)") -> "(({} (%1) %%userdata) => error)"
-    ident <- [a-zA-Z_][a-zA-Z0-9_]*
-    comment <- "--" [^%nl]*
-    ]]
-    for version=1,Parser.version
-        peg_file = io.open("nomsu.#{version}.peg")
-        if not peg_file and package.nomsupath
-            for path in package.nomsupath\gmatch("[^;]+")
-                peg_file = io.open(path.."/nomsu.#{version}.peg")
-                break if peg_file
-        assert(peg_file, "could not find nomsu .peg file")
-        nomsu_peg = peg_tidier\match(peg_file\read('*a'))
-        peg_file\close!
-        Parser.patterns[version] = re.compile(nomsu_peg, NOMSU_DEFS)
-
-_anon_chunk = 0
-Parser.parse = (nomsu_code, source=nil, version=nil)->
-    source or= nomsu_code.source
-    nomsu_code = tostring(nomsu_code)
-    unless source
-        source = Source("anonymous chunk ##{_anon_chunk}", 1, #nomsu_code)
-        _anon_chunk += 1
-    version or= nomsu_code\match("^#![^\n]*nomsu[ ]+-V[ ]*([0-9.]+)")
-    syntax_version = version and tonumber(version\match("^[0-9]+")) or Parser.version
-    userdata = {
-        errors: {}, :source, comments: {}
-    }
-    tree = Parser.patterns[syntax_version]\match(nomsu_code, nil, userdata)
-    if not tree or type(tree) == 'number'
-        error "In file #{colored.blue tostring(source or "<unknown>")} failed to parse:\n#{colored.onyellow colored.black nomsu_code}"
-
-    if next(userdata.errors)
-        keys = [k for k,v in pairs(userdata.errors)]
-        table.sort(keys)
-        errors = [userdata.errors[k] for k in *keys]
-        error("Errors occurred while parsing (v#{syntax_version}):\n\n"..table.concat(errors, "\n\n"), 0)
-
-    comments = [{comment:c, pos:p} for p,c in pairs(userdata.comments)]
-    -- Sort in descending order so we can pop the first comments off the end one at a time
-    table.sort comments, (a,b)-> a.pos > b.pos
-    comment_i = 1
-    walk_tree = (t)->
-        export comment_i
-        comment_buff = {}
-        while comments[#comments] and comments[#comments].pos <= t.source.start
-            table.insert(comment_buff, table.remove(comments))
-        for x in *t
-            if AST.is_syntax_tree x
-                walk_tree x
-        while comments[#comments] and comments[#comments].pos <= t.source.stop
-            table.insert(comment_buff, table.remove(comments))
-        t.comments = comment_buff if #comment_buff > 0
-    walk_tree tree
-
-    return tree
+Parser = {version:4, patterns:{}}
 
 Parser.is_operator = (s)->
     return not not (NOMSU_DEFS.operator_char^1 * -1)\match(s)
diff --git a/pretty_errors.lua b/pretty_errors.lua
index 7402703..ae6b48f 100644
--- a/pretty_errors.lua
+++ b/pretty_errors.lua
@@ -42,6 +42,7 @@ format_error = function(err)
     err_msg = err_msg .. "\n\027[2m" .. tostring(fmt_str:format(err_linenum)) .. tostring(err_line) .. "\027[0m"
   end
   local _, err_linenum_end, err_linepos_end = string2.line_at(err.source, err.stop)
+  err_linenum_end = err_linenum_end or err_linenum
   if err_linenum_end == err_linenum then
     err_msg = err_msg .. "\n" .. tostring(pointer)
   else
diff --git a/pretty_errors.moon b/pretty_errors.moon
index 3b583b7..b0d81f9 100644
--- a/pretty_errors.moon
+++ b/pretty_errors.moon
@@ -34,6 +34,7 @@ format_error = (err)->
         err_line = "\027[0m#{before}\027[41;30m#{during}#{nl_indicator}\027[0m#{after}"
         err_msg ..= "\n\027[2m#{fmt_str\format(err_linenum)}#{err_line}\027[0m"
     _, err_linenum_end, err_linepos_end = string2.line_at(err.source, err.stop)
+    err_linenum_end or= err_linenum
     if err_linenum_end == err_linenum
         err_msg ..= "\n#{pointer}"
     else