Use "using" instead of "gtk" and "import"

- Having one keyword for both is less syntax to remember
- I might use "include" as a keyword in the future, which would make
  "import" confusing, so use "using" instead

README.md

@@ -21,10 +21,8 @@ Here is what [the libshumate demo's UI definition](https://gitlab.gnome.org/GNOM
 looks like ported to this new format:
 
 ```
-gtk 4.0;
+using Gtk 4.0;
-
+using Shumate 1.0;
-import Adw 1.0;
-import Shumate 1.0;
 
 template ShumateDemoWindow : Gtk.ApplicationWindow {
   can-focus: yes;

gtkblueprinttool/lsp.py

@@ -18,7 +18,7 @@
 # SPDX-License-Identifier: LGPL-3.0-or-later
 
 
-import json, sys
+import json, sys, traceback
 
 from .errors import PrintableError, CompileError, MultipleErrors
 from .lsp_enums import *
@@ -61,7 +61,7 @@ class LanguageServer:
                 if method in self.commands:
                     self.commands[method](self, id, params)
         except Exception as e:
-            self._log(e)
+            self._log(traceback.format_exc())
 
 
     def _send(self, data):

gtkblueprinttool/parse_tree.py

@@ -408,6 +408,21 @@ class UseNumber(ParseNode):
         return True
 
 
+class UseNumberText(ParseNode):
+    """ ParseNode that matches a number, but sets its *original text* it in a
+    key=value pair on the containing match group. """
+    def __init__(self, key):
+        self.key = key
+
+    def _parse(self, ctx: ParseContext):
+        token = ctx.next_token()
+        if token.type != TokenType.NUMBER:
+            return False
+
+        ctx.set_group_val(self.key, str(token), token)
+        return True
+
+
 class UseQuoted(ParseNode):
     """ ParseNode that matches a quoted string and sets it in a key=value pair
     on the containing match group. """

gtkblueprinttool/parser.py

@@ -30,9 +30,9 @@ def parse(tokens) -> ast.UI:
     gtk_directive = Group(
         ast.GtkDirective,
         Sequence(
-            Keyword("gtk"),
+            Keyword("using"),
-            Fail(UseNumber(None), "Version number must be in quotation marks"),
+            Keyword("Gtk"),
-            UseQuoted("version").expected("a version number for GTK"),
+            UseNumberText("version").expected("a version number for GTK"),
             StmtEnd().expected("`;`"),
         )
     )
@@ -40,10 +40,9 @@ def parse(tokens) -> ast.UI:
     import_statement = Group(
         ast.Import,
         Sequence(
-            Keyword("import"),
+            Keyword("using"),
             UseIdent("namespace").expected("a GIR namespace"),
-            Fail(UseNumber(None), "Version number must be in quotation marks"),
+            UseNumberText("version").expected("a version number"),
-            UseQuoted("version").expected("a version number"),
             StmtEnd().expected("`;`"),
         )
     ).recover()
@@ -173,7 +172,7 @@ def parse(tokens) -> ast.UI:
     ui = Group(
         ast.UI,
         Sequence(
-            gtk_directive.err("File must start with a gtk directive (e.g. `gtk 4.0;`)"),
+            gtk_directive.err("File must start with a \"using gtk\" directive (e.g. `using Gtk 4.0;`)"),
             ZeroOrMore(import_statement),
             ZeroOrMore(AnyOf(
                 template,

gtkblueprinttool/utils.py

@@ -68,6 +68,8 @@ def did_you_mean(word: str, options: [str]) -> T.Optional[str]:
 
 
 def idx_to_pos(idx: int, text: str) -> (int, int):
+    if idx == 0:
+        return (0, 0)
     sp = text[:idx].splitlines(keepends=True)
     line_num = len(sp)
     col_num = len(sp[-1])