Use Optional

packages/combinator/example/basic_auth.dart

@@ -18,7 +18,7 @@ final Parser<Map<String, String>> credentials = chain<String>([
   match<String>(':'),
   string.opt(),
 ]).map<Map<String, String>>(
-    (r) => {'username': r.value![0]!, 'password': r.value![2]!});
+    (r) => {'username': r.value![0], 'password': r.value![2]});
 
 /// We can actually embed a parser within another parser.
 ///

packages/combinator/example/calculator.dart

@@ -24,7 +24,7 @@ Parser<num> calculatorGrammar() {
         expr.space(),
         match<Null>(op).space() as Parser<num>,
         expr.space(),
-      ]).map((r) => f(r.value![0]!, r.value![2]!)),
+      ]).map((r) => f(r.value![0], r.value![2])),
     );
   }
 

packages/combinator/lib/src/combinator/advance.dart

@@ -7,7 +7,7 @@ class _Advance<T> extends Parser<T> {
   _Advance(this.parser, this.amount);
 
   @override
-  ParseResult<T?> __parse(ParseArgs args) {
+  ParseResult<T> __parse(ParseArgs args) {
     var result = parser._parse(args.increaseDepth()).change(parser: this);
     if (result.successful) args.scanner.position += amount;
     return result;

packages/combinator/lib/src/combinator/any.dart

@@ -21,7 +21,7 @@ class _Any<T> extends Parser<T> {
   _Any(this.parsers, this.backtrack, this.errorMessage, this.severity);
 
   @override
-  ParseResult<T?> _parse(ParseArgs args) {
+  ParseResult<T> _parse(ParseArgs args) {
     var inactive = parsers
         .where((p) => !args.trampoline.isActive(p, args.scanner.position));
 

packages/combinator/lib/src/combinator/cache.dart

@@ -1,13 +1,13 @@
 part of lex.src.combinator;
 
 class _Cache<T> extends Parser<T> {
-  final Map<int, ParseResult<T?>> _cache = {};
+  final Map<int, ParseResult<T>> _cache = {};
   final Parser<T> parser;
 
   _Cache(this.parser);
 
   @override
-  ParseResult<T?> __parse(ParseArgs args) {
+  ParseResult<T> __parse(ParseArgs args) {
     return _cache.putIfAbsent(args.scanner.position, () {
       return parser._parse(args.increaseDepth());
     }).change(parser: this);

packages/combinator/lib/src/combinator/chain.dart

@@ -3,9 +3,9 @@ part of lex.src.combinator;
 /// Expects to parse a sequence of [parsers].
 ///
 /// If [failFast] is `true` (default), then the first failure to parse will abort the parse.
-ListParser<T?> chain<T>(Iterable<Parser<T>> parsers,
+ListParser<T> chain<T>(Iterable<Parser<T>> parsers,
     {bool failFast: true, SyntaxErrorSeverity? severity}) {
-  return _Chain<T?>(
+  return _Chain<T>(
       parsers, failFast != false, severity ?? SyntaxErrorSeverity.error);
 }
 
@@ -17,7 +17,7 @@ class _Alt<T> extends Parser<T> {
   _Alt(this.parser, this.errorMessage, this.severity);
 
   @override
-  ParseResult<T?> __parse(ParseArgs args) {
+  ParseResult<T> __parse(ParseArgs args) {
     var result = parser._parse(args.increaseDepth());
     return result.successful
         ? result
@@ -33,7 +33,7 @@ class _Alt<T> extends Parser<T> {
   }
 }
 
-class _Chain<T> extends ListParser<T?> {
+class _Chain<T> extends ListParser<T> {
   final Iterable<Parser<T>> parsers;
   final bool failFast;
   final SyntaxErrorSeverity severity;
@@ -41,7 +41,7 @@ class _Chain<T> extends ListParser<T?> {
   _Chain(this.parsers, this.failFast, this.severity);
 
   @override
-  ParseResult<List<T?>?> __parse(ParseArgs args) {
+  ParseResult<List<T>> __parse(ParseArgs args) {
     var errors = <SyntaxError>[];
     var results = <T?>[];
     var spans = <FileSpan>[];
@@ -61,7 +61,10 @@ class _Chain<T> extends ListParser<T?> {
         successful = false;
       }
 
+      //TODO: To be looked at
+      //if (result.value != null) {
       results.add(result.value);
+      //}
 
       if (result.span != null) {
         spans.add(result.span!);
@@ -74,14 +77,14 @@ class _Chain<T> extends ListParser<T?> {
       span = spans.reduce((a, b) => a.expand(b));
     }
 
-    return ParseResult<List<T?>?>(
+    return ParseResult<List<T>>(
       args.trampoline,
       args.scanner,
       this,
       successful,
       errors,
       span: span,
-      value: List<T?>.unmodifiable(results),
+      value: List<T>.unmodifiable(results),
     );
   }
 

packages/combinator/lib/src/combinator/check.dart

@@ -9,7 +9,7 @@ class _Check<T> extends Parser<T> {
   _Check(this.parser, this.matcher, this.errorMessage, this.severity);
 
   @override
-  ParseResult<T?> __parse(ParseArgs args) {
+  ParseResult<T> __parse(ParseArgs args) {
     var matchState = {};
     var result = parser._parse(args.increaseDepth()).change(parser: this);
     if (!result.successful)

packages/combinator/lib/src/combinator/combinator.dart

@@ -7,6 +7,7 @@ import 'package:matcher/matcher.dart';
 import 'package:source_span/source_span.dart';
 import 'package:string_scanner/string_scanner.dart';
 import 'package:tuple/tuple.dart';
+import 'package:optional/optional.dart';
 import '../error.dart';
 
 part 'any.dart';
@@ -67,9 +68,9 @@ class ParseArgs {
 
 /// A parser combinator, which can parse very complicated grammars in a manageable manner.
 abstract class Parser<T> {
-  ParseResult<T?> __parse(ParseArgs args);
+  ParseResult<T> __parse(ParseArgs args);
 
-  ParseResult<T?> _parse(ParseArgs args) {
+  ParseResult<T> _parse(ParseArgs args) {
     var pos = args.scanner.position;
 
     if (args.trampoline.hasMemoized(this, pos))
@@ -86,7 +87,7 @@ abstract class Parser<T> {
   }
 
   /// Parses text from a [SpanScanner].
-  ParseResult<T?> parse(SpanScanner scanner, [int depth = 1]) {
+  ParseResult<T> parse(SpanScanner scanner, [int depth = 1]) {
     var args = ParseArgs(Trampoline(), scanner, depth);
     return _parse(args);
   }
@@ -105,7 +106,7 @@ abstract class Parser<T> {
 
   // TODO: Type issue
   /// Runs the given function, which changes the returned [ParseResult] into one relating to a [U] object.
-  Parser<U> change<U>(ParseResult<U?> Function(ParseResult<T?>) f) {
+  Parser<U> change<U>(ParseResult<U> Function(ParseResult<T>) f) {
     return _Change<T, U>(this, f);
   }
 
@@ -128,7 +129,7 @@ abstract class Parser<T> {
   }
 
   /// Transforms the parse result using a unary function.
-  Parser<U> map<U>(U Function(ParseResult<T?>) f) {
+  Parser<U> map<U>(U Function(ParseResult<T>) f) {
     return _Map<T, U>(this, f);
   }
 
@@ -171,7 +172,7 @@ abstract class Parser<T> {
   Parser<T> or<U>(Parser<T> other) => any<T>([this, other]);
 
   /// Parses this sequence one or more times.
-  ListParser<T?> plus() => times(1, exact: false);
+  ListParser<T> plus() => times(1, exact: false);
 
   /// Safely escapes this parser when an error occurs.
   ///
@@ -207,11 +208,11 @@ abstract class Parser<T> {
     });
   }
 
-  Parser<T?> surroundedByCurlyBraces({T? defaultValue}) => opt()
+  Parser<T> surroundedByCurlyBraces({required T defaultValue}) => opt()
       .surroundedBy(match('{').space(), match('}').space())
       .map((r) => r.value ?? defaultValue);
 
-  Parser<T?> surroundedBySquareBrackets({T? defaultValue}) => opt()
+  Parser<T> surroundedBySquareBrackets({required T defaultValue}) => opt()
       .surroundedBy(match('[').space(), match(']').space())
       .map((r) => r.value ?? defaultValue);
 
@@ -336,7 +337,9 @@ class Trampoline {
   }
 
   bool isActive(Parser parser, int position) {
-    if (!_active.containsKey(parser)) return false;
+    if (!_active.containsKey(parser)) {
+      return false;
+    }
     var q = _active[parser]!;
     if (q.isEmpty) return false;
     //return q.contains(position);

packages/combinator/lib/src/combinator/compare.dart

@@ -7,8 +7,8 @@ class _Compare<T> extends ListParser<T> {
   _Compare(this.parser, this.compare);
 
   @override
-  ParseResult<List<T>?> __parse(ParseArgs args) {
+  ParseResult<List<T>> __parse(ParseArgs args) {
-    ParseResult<List<T>?> result = parser._parse(args.increaseDepth());
+    ParseResult<List<T>> result = parser._parse(args.increaseDepth());
     if (!result.successful) return result;
 
     result = result.change(

packages/combinator/lib/src/combinator/fold_errors.dart

@@ -7,7 +7,7 @@ class _FoldErrors<T> extends Parser<T> {
   _FoldErrors(this.parser, this.equal);
 
   @override
-  ParseResult<T?> __parse(ParseArgs args) {
+  ParseResult<T> __parse(ParseArgs args) {
     var result = parser._parse(args.increaseDepth()).change(parser: this);
     var errors = result.errors.fold<List<SyntaxError>>([], (out, e) {
       if (!out.any((b) => equal(e, b))) out.add(e);

packages/combinator/lib/src/combinator/longest.dart

@@ -16,7 +16,7 @@ class _Longest<T> extends Parser<T> {
   _Longest(this.parsers, this.errorMessage, this.severity);
 
   @override
-  ParseResult<T?> _parse(ParseArgs args) {
+  ParseResult<T> _parse(ParseArgs args) {
     var inactive = parsers
         .toList()
         .where((p) => !args.trampoline.isActive(p, args.scanner.position));
@@ -27,7 +27,7 @@ class _Longest<T> extends Parser<T> {
 
     int replay = args.scanner.position;
     var errors = <SyntaxError>[];
-    var results = <ParseResult<T?>>[];
+    var results = <ParseResult<T>>[];
 
     for (var parser in inactive) {
       var result = parser._parse(args.increaseDepth());
@@ -59,10 +59,10 @@ class _Longest<T> extends Parser<T> {
   }
 
   @override
-  ParseResult<T?> __parse(ParseArgs args) {
+  ParseResult<T> __parse(ParseArgs args) {
     int replay = args.scanner.position;
     var errors = <SyntaxError>[];
-    var results = <ParseResult<T?>>[];
+    var results = <ParseResult<T>>[];
 
     for (var parser in parsers) {
       var result = parser._parse(args.increaseDepth());

packages/combinator/lib/src/combinator/map.dart

@@ -2,14 +2,14 @@ part of lex.src.combinator;
 
 class _Map<T, U> extends Parser<U> {
   final Parser<T> parser;
-  final U Function(ParseResult<T?>) f;
+  final U Function(ParseResult<T>) f;
 
   _Map(this.parser, this.f);
 
   @override
-  ParseResult<U?> __parse(ParseArgs args) {
+  ParseResult<U> __parse(ParseArgs args) {
     var result = parser._parse(args.increaseDepth());
-    return ParseResult<U?>(
+    return ParseResult<U>(
       args.trampoline,
       args.scanner,
       this,
@@ -34,12 +34,12 @@ class _Map<T, U> extends Parser<U> {
 
 class _Change<T, U> extends Parser<U> {
   final Parser<T> parser;
-  final ParseResult<U?> Function(ParseResult<T?>) f;
+  final ParseResult<U> Function(ParseResult<T>) f;
 
   _Change(this.parser, this.f);
 
   @override
-  ParseResult<U?> __parse(ParseArgs args) {
+  ParseResult<U> __parse(ParseArgs args) {
     return f(parser._parse(args.increaseDepth())).change(parser: this);
   }
 

packages/combinator/lib/src/combinator/max_depth.dart

@@ -7,7 +7,7 @@ class _MaxDepth<T> extends Parser<T> {
   _MaxDepth(this.parser, this.cap);
 
   @override
-  ParseResult<T?> __parse(ParseArgs args) {
+  ParseResult<T> __parse(ParseArgs args) {
     if (args.depth > cap) {
       return ParseResult<T>(args.trampoline, args.scanner, this, false, []);
     }

packages/combinator/lib/src/combinator/negate.dart

@@ -8,7 +8,7 @@ class _Negate<T> extends Parser<T> {
   _Negate(this.parser, this.errorMessage, this.severity);
 
   @override
-  ParseResult<T?> __parse(ParseArgs args) {
+  ParseResult<T> __parse(ParseArgs args) {
     var result = parser._parse(args.increaseDepth()).change(parser: this);
 
     if (!result.successful) {

packages/combinator/lib/src/combinator/opt.dart

@@ -7,7 +7,7 @@ class _Opt<T> extends Parser<T> {
   _Opt(this.parser, this.backtrack);
 
   @override
-  ParseResult<T?> __parse(ParseArgs args) {
+  ParseResult<T> __parse(ParseArgs args) {
     var replay = args.scanner.position;
     var result = parser._parse(args.increaseDepth());
 
@@ -35,9 +35,9 @@ class _ListOpt<T> extends ListParser<T> {
   _ListOpt(this.parser, this.backtrack);
 
   @override
-  ParseResult<List<T>?> __parse(ParseArgs args) {
+  ParseResult<List<T>> __parse(ParseArgs args) {
     var replay = args.scanner.position;
-    ParseResult<List<T>?> result = parser._parse(args.increaseDepth());
+    ParseResult<List<T>> result = parser._parse(args.increaseDepth());
 
     if (!result.successful) args.scanner.position = replay;
 

packages/combinator/lib/src/combinator/reduce.dart

@@ -7,8 +7,8 @@ class _Reduce<T> extends Parser<T> {
   _Reduce(this.parser, this.combine);
 
   @override
-  ParseResult<T?> __parse(ParseArgs args) {
+  ParseResult<T> __parse(ParseArgs args) {
-    ParseResult<List<T>?> result = parser._parse(args.increaseDepth());
+    ParseResult<List<T>> result = parser._parse(args.increaseDepth());
 
     if (!result.successful)
       return ParseResult<T>(

packages/combinator/lib/src/combinator/reference.dart

@@ -15,14 +15,14 @@ class Reference<T> extends Parser<T> {
   }
 
   @override
-  ParseResult<T?> __parse(ParseArgs args) {
+  ParseResult<T> __parse(ParseArgs args) {
     if (_parser == null)
       throw StateError('There is no parser assigned to this reference.');
     return _parser!._parse(args);
   }
 
   @override
-  ParseResult<T?> _parse(ParseArgs args) {
+  ParseResult<T> _parse(ParseArgs args) {
     if (_parser == null)
       throw StateError('There is no parser assigned to this reference.');
     return _parser!._parse(args);

packages/combinator/lib/src/combinator/repeat.dart

@@ -12,12 +12,12 @@ class _Repeat<T> extends ListParser<T> {
       this.backtrack, this.severity);
 
   @override
-  ParseResult<List<T>?> __parse(ParseArgs args) {
+  ParseResult<List<T>> __parse(ParseArgs args) {
     var errors = <SyntaxError>[];
     var results = <T>[];
     var spans = <FileSpan>[];
     int success = 0, replay = args.scanner.position;
-    ParseResult<T?> result;
+    ParseResult<T> result;
 
     do {
       result = parser._parse(args.increaseDepth());
@@ -51,7 +51,7 @@ class _Repeat<T> extends ListParser<T> {
     } else if (success > count && exact) {
       if (backtrack) args.scanner.position = replay;
 
-      return ParseResult<List<T>?>(args.trampoline, args.scanner, this, false, [
+      return ParseResult<List<T>>(args.trampoline, args.scanner, this, false, [
         SyntaxError(
           severity,
           tooMany,

packages/combinator/lib/src/combinator/safe.dart

@@ -10,7 +10,7 @@ class _Safe<T> extends Parser<T> {
   _Safe(this.parser, this.backtrack, this.errorMessage, this.severity);
 
   @override
-  ParseResult<T?> __parse(ParseArgs args) {
+  ParseResult<T> __parse(ParseArgs args) {
     var replay = args.scanner.position;
 
     try {

packages/combinator/lib/src/combinator/value.dart

@@ -2,12 +2,12 @@ part of lex.src.combinator;
 
 class _Value<T> extends Parser<T> {
   final Parser<T> parser;
-  final T Function(ParseResult<T?>) f;
+  final T Function(ParseResult<T>) f;
 
   _Value(this.parser, this.f);
 
   @override
-  ParseResult<T?> __parse(ParseArgs args) {
+  ParseResult<T> __parse(ParseArgs args) {
     var result = parser._parse(args.increaseDepth()).change(parser: this);
     return result.successful ? result.change(value: f(result)) : result;
   }

packages/combinator/pubspec.yaml

@@ -15,5 +15,6 @@ dependencies:
   source_span: ^1.8.1
   string_scanner: ^1.1.0
   tuple: ^2.0.0
+  optional: ^6.0.0-nullsafety.2
 dev_dependencies:
   test: ^1.17.3

packages/combinator/test/list_test.dart

@@ -11,11 +11,11 @@ main() {
   var numbers = number.plus();
 
   test('sort', () {
-    var parser = numbers.sort((a, b) => a!.compareTo(b!));
+    var parser = numbers.sort((a, b) => a.compareTo(b));
     expect(parser.parse(scan('21,2,3,34,20')).value, [2, 3, 20, 21, 34]);
   });
   test('reduce', () {
-    var parser = numbers.reduce((a, b) => a! + b!);
+    var parser = numbers.reduce((a, b) => a + b);
     expect(parser.parse(scan('21,2,3,34,20')).value, 80);
     expect(parser.parse(scan('not numbers')).value, isNull);
   });

packages/framework/lib/src/core/driver.dart

@@ -139,7 +139,8 @@ abstract class Driver<
               pipeline.handlers,
               resolved.fold<Map<String, dynamic>>(
                   <String, dynamic>{}, (out, r) => out..addAll(r.allParams)),
-              (resolved.isEmpty ? null : resolved.first.parseResult)!,
+              //(resolved.isEmpty ? null : resolved.first.parseResult),
+              resolved.first.parseResult,
               pipeline,
             );
           }

packages/framework/pubspec.yaml

@@ -22,10 +22,11 @@ dependencies:
       ref: sdk-2.12.x_nnbd
       path: packages/model
   angel_route:
-    git: 
+    path: ../route
-      url: https://github.com/dukefirehawk/angel.git
+#    git: 
-      ref: sdk-2.12.x_nnbd
+#      url: https://github.com/dukefirehawk/angel.git
-      path: packages/route
+#      ref: sdk-2.12.x_nnbd
+#      path: packages/route
   charcode: ^1.2.0
   combinator:
     git: 

packages/route/lib/src/router.dart

@@ -311,7 +311,7 @@ class Router<T> {
           if (parseResult != null) {
             if (parseResult.successful && scanner.isDone) {
               var tailResult = parseResult.value?.tail ?? '';
-              print(tailResult);
+              //print(tailResult);
               var result = RoutingResult<T>(
                   parseResult: parseResult,
                   params: parseResult.value!.params,
@@ -334,13 +334,13 @@ class Router<T> {
 
   /// Returns the result of [resolve] with [path] passed as
   /// both `absolute` and `relative`.
-  Iterable<RoutingResult<T?>> resolveAbsolute(String path,
+  Iterable<RoutingResult<T>> resolveAbsolute(String path,
           {String method = 'GET', bool strip = true}) =>
       resolveAll(path, path, method: method, strip: strip);
 
   /// Finds every possible [Route] that matches the given path,
   /// with the given method.
-  Iterable<RoutingResult<T?>> resolveAll(String absolute, String relative,
+  Iterable<RoutingResult<T>> resolveAll(String absolute, String relative,
       {String method = 'GET', bool strip = true}) {
     if (_useCache == true) {
       return _cache.putIfAbsent('$method$absolute',

packages/route/lib/src/routing_result.dart

@@ -3,7 +3,7 @@ part of angel_route.src.router;
 /// Represents a complex result of navigating to a path.
 class RoutingResult<T> {
   /// The parse result that matched the given sub-path.
-  final ParseResult<RouteResult?> parseResult;
+  final ParseResult<RouteResult> parseResult;
 
   /// A nested instance, if a sub-path was matched.
   final Iterable<RoutingResult<T>> nested;
@@ -47,10 +47,10 @@ class RoutingResult<T> {
   }
 
   /// All handlers on this sub-path and its children.
-  List<T?> get allHandlers {
+  List<T> get allHandlers {
-    final handlers = <T?>[];
+    final handlers = <T>[];
 
-    void crawl(RoutingResult<T?> result) {
+    void crawl(RoutingResult<T> result) {
       handlers.addAll(result.handlers);
 
       if (result.nested.isNotEmpty == true) {

packages/route/pubspec.yaml

@@ -7,11 +7,11 @@ environment:
   sdk: '>=2.12.0 <3.0.0'
 dependencies:
   combinator:
-#    path: ../combinator
+    path: ../combinator
-    git: 
+#    git: 
-      url: https://github.com/dukefirehawk/angel.git
+#      url: https://github.com/dukefirehawk/angel.git
-      ref: sdk-2.12.x_nnbd
+#      ref: sdk-2.12.x_nnbd
-      path: packages/combinator
+#      path: packages/combinator
   string_scanner: ^1.0.0
 dev_dependencies:
   build_runner: ^1.11.5