Better parse error reporting.

core/collections.nom

@@ -110,8 +110,8 @@ immediately
         return %flat
 
     parse [entries in %dict] as: {key:%k, value:%v} for %k = %v in %dict
-    parse [keys in %dict] as: %k for %k = %v in %dict
+    parse [keys in %dict, keys of %dict] as: %k for %k = %v in %dict
-    parse [values in %dict] as: %v for %k = %v in %dict
+    parse [values in %dict, values of %dict] as: %v for %k = %v in %dict
 
 # Metatable stuff
 immediately

nomsu.lua

@@ -190,6 +190,10 @@ do
     if seen_errors[start_pos] then
       return true
     end
+    if utils.size(seen_errors) >= 10 then
+      seen_errors[start_pos + 1] = colored.bright(colored.yellow(colored.onred("Too many errors, canceling parsing...")))
+      return #src
+    end
     local err_pos = start_pos
     local text_loc = userdata.source:sub(err_pos, err_pos)
     local line_no = text_loc:get_line_number()
@@ -197,14 +201,16 @@ do
     local prev_line = line_no == 1 and "" or src:sub(LINE_STARTS[src][line_no - 1] or 1, LINE_STARTS[src][line_no] - 2)
     local err_line = src:sub(LINE_STARTS[src][line_no], (LINE_STARTS[src][line_no + 1] or 0) - 2)
     local next_line = src:sub(LINE_STARTS[src][line_no + 1] or -1, (LINE_STARTS[src][line_no + 2] or 0) - 2)
-    local pointer = ("-"):rep(err_pos - LINE_STARTS[src][line_no]) .. "^"
+    local i = err_pos - LINE_STARTS[src][line_no]
-    err_msg = (err_msg or "Parse error") .. " at " .. tostring(userdata.source.filename) .. ":" .. tostring(line_no) .. ":\n"
+    local pointer = ("-"):rep(i) .. "^"
+    err_msg = colored.bright(colored.yellow(colored.onred((err_msg or "Parse error") .. " at " .. tostring(userdata.source.filename) .. ":" .. tostring(line_no) .. ":")))
     if #prev_line > 0 then
-      err_msg = err_msg .. ("\n" .. prev_line)
+      err_msg = err_msg .. ("\n" .. colored.dim(prev_line))
     end
-    err_msg = err_msg .. "\n" .. tostring(err_line) .. "\n" .. tostring(pointer)
+    err_line = colored.white(err_line:sub(1, i)) .. colored.bright(colored.red(err_line:sub(i + 1, i + 1))) .. colored.dim(err_line:sub(i + 2, -1))
+    err_msg = err_msg .. "\n" .. tostring(err_line) .. "\n" .. tostring(colored.red(pointer))
     if #next_line > 0 then
-      err_msg = err_msg .. ("\n" .. next_line)
+      err_msg = err_msg .. ("\n" .. colored.dim(next_line))
     end
     seen_errors[start_pos] = err_msg
     return true
@@ -326,7 +332,8 @@ do
           end
           errors = _accum_0
         end
-        error(concat(errors, "\n\n"), 0)
+        io.stderr:write(concat(errors, "\n\n") .. "\n")
+        os.exit()
       end
       return tree
     end,

nomsu.moon

@@ -164,6 +164,9 @@ NOMSU_DEFS = with {}
         seen_errors = userdata.errors
         if seen_errors[start_pos]
             return true
+        if utils.size(seen_errors) >= 10
+            seen_errors[start_pos+1] = colored.bright colored.yellow colored.onred "Too many errors, canceling parsing..."
+            return #src
         err_pos = start_pos
         --if src\sub(err_pos,err_pos)\match("[\r\n]")
         --    err_pos += #src\match("[ \t\n\r]*", err_pos)
@@ -173,11 +176,13 @@ NOMSU_DEFS = with {}
         prev_line = line_no == 1 and "" or src\sub(LINE_STARTS[src][line_no-1] or 1, LINE_STARTS[src][line_no]-2)
         err_line = src\sub(LINE_STARTS[src][line_no], (LINE_STARTS[src][line_no+1] or 0)-2)
         next_line = src\sub(LINE_STARTS[src][line_no+1] or -1, (LINE_STARTS[src][line_no+2] or 0)-2)
-        pointer = ("-")\rep(err_pos-LINE_STARTS[src][line_no]) .. "^"
+        i = err_pos-LINE_STARTS[src][line_no]
-        err_msg = (err_msg or "Parse error").." at #{userdata.source.filename}:#{line_no}:\n"
+        pointer = ("-")\rep(i) .. "^"
-        if #prev_line > 0 then err_msg ..= "\n"..prev_line
+        err_msg = colored.bright colored.yellow colored.onred (err_msg or "Parse error").." at #{userdata.source.filename}:#{line_no}:"
-        err_msg ..= "\n#{err_line}\n#{pointer}"
+        if #prev_line > 0 then err_msg ..= "\n"..colored.dim(prev_line)
-        if #next_line > 0 then err_msg ..= "\n"..next_line
+        err_line = colored.white(err_line\sub(1, i))..colored.bright(colored.red(err_line\sub(i+1,i+1)))..colored.dim(err_line\sub(i+2,-1))
+        err_msg ..= "\n#{err_line}\n#{colored.red pointer}"
+        if #next_line > 0 then err_msg ..= "\n"..colored.dim(next_line)
         --error(err_msg)
         seen_errors[start_pos] = err_msg
         return true
@@ -329,7 +334,8 @@ class NomsuCompiler
             keys = utils.keys(userdata.errors)
             table.sort(keys)
             errors = [userdata.errors[k] for k in *keys]
-            error(concat(errors, "\n\n"), 0)
+            io.stderr\write(concat(errors, "\n\n").."\n")
+            os.exit!
         
         return tree
 

nomsu.peg

@@ -10,9 +10,9 @@ shebang: "#!" [^%nl]* (!. / %nl)
 inline_block (Block):
     {| inline_statement (%ws* ";" %ws*  inline_statement)+ |}
 block (Block):
-    {| statement (nodent (statement / (({} ([^%nl]* -> "Error while parsing block line") %userdata) => error)))+ |}
+    {| statement (nodent (statement / (({} ([^%nl]* -> "Unexpected character while parsing block line") %userdata) => error)))+ |}
 
-statement: (action / expression) (eol / (({} ([^%nl]* -> "Error while parsing line") %userdata) => error))
+statement: (action / expression) (eol / (({} ([^%nl]* -> "Unexpected character while parsing line") %userdata) => error))
 inline_statement: inline_action / inline_expression
 
 noindex_inline_expression:
@@ -21,8 +21,8 @@ noindex_inline_expression:
             %ws* (inline_block / inline_action / inline_expression) %ws*
             (comma %ws* (inline_block / inline_action / inline_expression) %ws*)*
         (")"
-            / (({} ((!. / &%nl) -> 'Expected to find a ) before the end of the line') %userdata) => error)
+            / (({} ((!. / &%nl) -> 'Line ended without finding a closing )-parenthesis') %userdata) => error)
-            / (({} ([^%nl]* -> 'Error while parsing subexpression') %userdata) => error)
+            / (({} ([^%nl]* -> 'Unexpected character while parsing subexpression') %userdata) => error)
         )
       )
 inline_expression:
@@ -31,14 +31,21 @@ indented_expression:
     indented_text / indented_nomsu / indented_list / indented_dict
     / ("(..)"? indent
         (block / action / expression)
-        (dedent / (({} (non_dedent_error -> "Error while parsing indented expression") %userdata) => error))
+        (dedent / (({} (non_dedent_error -> "Unexpected character while parsing indented expression") %userdata) => error))
       )
 expression:
-    inline_expression / (":" %ws* (inline_block / inline_action / inline_expression) eol) / indented_expression
+    inline_expression
+    / (":" %ws* ((inline_block / inline_action / inline_expression) eol
+        / (({} (eol -> "Missing expression after the ':'") %userdata) => error)))
+    / indented_expression
 
 inline_nomsu (EscapedNomsu): "\" {| inline_expression |}
 indented_nomsu (EscapedNomsu):
-    "\" {| (noindex_inline_expression / (":" %ws* (inline_block / inline_action / inline_expression) eol) / indented_expression) |}
+    "\" {|
+        noindex_inline_expression
+        / (":" %ws* ((inline_block / inline_action / inline_expression) eol
+             / (({} (eol -> "Missing expression after the ':'") %userdata) => error)))
+        / indented_expression |}
 
 index_chain (IndexChain):
     {| noindex_inline_expression ("." (text_word / noindex_inline_expression))+ |}
@@ -47,7 +54,8 @@ index_chain (IndexChain):
 inline_action (Action):
     {|
     (inline_expression %ws*)* word (%ws* (inline_expression / word))*
-    (%ws* ":" %ws* (inline_block / inline_action / inline_expression))?
+    (%ws* ":" %ws* (inline_block / inline_action / inline_expression
+        / (({} ('' -> "Missing expression after the ':'") %userdata) => error)))?
     |}
 action (Action):
     {| (expression (dotdot? %ws*))* word ((dotdot? %ws*) (expression / word))* |}
@@ -61,7 +69,10 @@ inline_text (Text):
     '"' {|
         ({~ (('\"' -> '"') / ('\\' -> '\') / %escaped_char / [^%nl\"])+ ~}
         / inline_text_interpolation)*
-    |} ('"' / (({} ([^%nl]*->'Failed to find a closing " mark on the same line') %userdata) => error))
+    |} ('"' / (
+        (({} (eol->'Line ended before finding a closing double quotation mark') %userdata) => error)
+       /(({} ([^%nl]*->'Unexpected character while parsing Text') %userdata) => error)
+    ))
 
 -- Have to use "%indent" instead of "indent" etc. to avoid messing up text lines that start with "#"
 indented_text (Text):
@@ -70,7 +81,7 @@ indented_text (Text):
         ({~
             (("\\" -> "\") / (("\" nodent "..") -> "")/ (%nl+ {~ %nodent -> "" ~}) / [^%nl\] / (!text_interpolation "\"))+
         ~} / text_interpolation)*
-    |} (((!.) %dedent) / (&(%nl %dedent)) / (({} (non_dedent_error -> "Error while parsing Text") %userdata) => error))
+    |} (((!.) %dedent) / (&(%nl %dedent)) / (({} (non_dedent_error -> "Unexpected character while parsing Text") %userdata) => error))
 inline_text_interpolation:
     "\" (
         variable / inline_list / inline_dict / inline_text
@@ -78,8 +89,8 @@ inline_text_interpolation:
             %ws* (inline_block / inline_action / inline_expression) %ws*
             (comma %ws* (inline_block / inline_action / inline_expression) %ws*)*
         (")"
-            / (({} (&%nl -> 'Expected to find a ")" before the end of the line') %userdata) => error)
+            / (({} (&%nl -> 'Line ended without finding a closing )-parenthesis') %userdata) => error)
-            / (({} ([^%nl]* -> 'Error while parsing text interpolation') %userdata) => error))
+            / (({} ([^%nl]* -> 'Unexpected character while parsing Text interpolation') %userdata) => error))
         )
     )
 text_interpolation:
@@ -94,12 +105,16 @@ variable (Var): "%" { (%ident_char+ ((!"'" %operator_char+) / %ident_char+)*)? }
 
 inline_list (List):
     !('[..]')
-    "[" %ws* {| (inline_list_item (comma inline_list_item)* comma?)? |} %ws*
+    "[" %ws*
-    ("]" / (({} ([^%nl]*->"Failed to find a closing ] on the same line") %userdata) => error))
+        {| (inline_list_item (comma inline_list_item)* comma?)? |} %ws*
+    ("]" / (","? (
+        (({} (eol->"Line ended before finding a closing ]-bracket") %userdata) => error)
+       /(({} ([^%nl]*->"Unexpected character while parsing List") %userdata) => error)
+    )))
 indented_list (List):
     "[..]" indent
         {| list_line (nodent list_line)* |}
-    (dedent / (({} (non_dedent_error -> "Error while parsing list") %userdata) => error))
+    (dedent / ((","? {} (non_dedent_error -> "Unexpected character while parsing List") %userdata) => error))
 list_line:
      ((action / expression) !comma)
      / (inline_list_item (comma list_line?)?)
@@ -107,20 +122,22 @@ inline_list_item: inline_block / inline_action / inline_expression
 
 inline_dict (Dict):
     !('{..}')
-    "{" %ws* {| (inline_dict_entry (comma inline_dict_entry)*)? |} %ws*
+    "{" %ws*
-    ("}"
+        {| (inline_dict_entry (comma inline_dict_entry)*)? |} %ws*
-      / (({} (%ws* comma? (!. / &%nl)->"Failed to find a closing } on the same line") %userdata) => error)
+    ("}" / (","? (
-      / (({} ([^%nl]*->"Error while parsing dictionary") %userdata) => error))
+        (({} (%ws* eol->"Line ended before finding a closing }-brace") %userdata) => error)
+      / (({} ([^%nl]*->"Unexpected character while parsing Dictionary") %userdata) => error)
+    )))
 indented_dict (Dict):
     "{..}" indent
         {| dict_line (nodent dict_line)* |}
-    (dedent / (({} (non_dedent_error -> "Error while parsing dict") %userdata) => error))
+    (dedent / ((","? {} (non_dedent_error -> "Unexpected character while parsing Dictionary") %userdata) => error))
 dict_line:
     (dict_entry !comma) / (inline_dict_entry (comma dict_line?)?)
 dict_entry(DictEntry):
-    {| dict_key %ws* ":" %ws* (action / expression) |}
+    {| dict_key (%ws* ":" %ws* (action / expression))? |}
 inline_dict_entry(DictEntry):
-    {| dict_key %ws* (":" %ws* (inline_block / inline_action / inline_expression)?) |}
+    {| dict_key (%ws* ":" %ws* (inline_block / inline_action / inline_expression)?)? |}
 dict_key:
     text_word / inline_expression