Inference through conditional expressions

lib/runtime/dart/convert.js

 var convert;
 (function(exports) {
   'use strict';
   let ASCII = dart.const(new AsciiCodec());
   let _ASCII_MASK = 127;
   let _allowInvalid = Symbol('_allowInvalid');
   let Codec$ = dart.generic(function(S, T) {
     class Codec extends core.Object {
       Codec() {
       }
@@ skipping 860 matching lines @@
   // Function _defaultToEncodable: (dynamic) → Object
   function _defaultToEncodable(object) {
     return dart.dsend(object, 'toJson');
   }
   let _seen = Symbol('_seen');
   let _checkCycle = Symbol('_checkCycle');
   let _removeSeen = Symbol('_removeSeen');
   class _JsonStringifier extends core.Object {
     _JsonStringifier(_toEncodable) {
       this[_seen] = new core.List();
-      this[_toEncodable$] = dart.as(_toEncodable != null ? _toEncodable : _defaultToEncodable, core.Function);
+      this[_toEncodable$] = _toEncodable != null ? _toEncodable : _defaultToEncodable;
     }
     static hexDigit(x) {
       return dart.notNull(x) < 10 ? 48 + dart.notNull(x) : 87 + dart.notNull(x);
     }
     writeStringContent(s) {
       let offset = 0;
       let length = s.length;
       for (let i = 0; dart.notNull(i) < dart.notNull(length); i = dart.notNull(i) + 1) {
         let charCode = s.codeUnitAt(i);
         if (dart.notNull(charCode) > dart.notNull(_JsonStringifier.BACKSLASH))
@@ skipping 1463 matching lines @@
   let _parent = Symbol('_parent');
   class _JsonMapKeyIterable extends _internal.ListIterable {
     _JsonMapKeyIterable(parent) {
       this[_parent] = parent;
       super.ListIterable();
     }
     get [core.$length]() {
       return this[_parent].length;
     }
     [core.$elementAt](index) {
-      return dart.as(this[_parent][_isUpgraded] ? this[_parent].keys[core.$elementAt](index) : this[_parent][_computeKeys]()[core.$get](index), core.String);
+      return this[_parent][_isUpgraded] ? dart.as(this[_parent].keys[core.$elementAt](index), core.String) : this[_parent][_computeKeys]()[core.$get](index);
     }
     get [core.$iterator]() {
-      return dart.as(this[_parent][_isUpgraded] ? this[_parent].keys[core.$iterator] : this[_parent][_computeKeys]()[core.$iterator], core.Iterator);
+      return this[_parent][_isUpgraded] ? this[_parent].keys[core.$iterator] : this[_parent][_computeKeys]()[core.$iterator];
     }
     [core.$contains](key) {
       return this[_parent].containsKey(key);
     }
   }
   class _JsonDecoderSink extends _StringSinkConversionSink {
     _JsonDecoderSink(reviver, sink) {
       this[_reviver] = reviver;
       this[_sink] = sink;
       super._StringSinkConversionSink(new core.StringBuffer());
@@ skipping 41 matching lines @@
   exports.LineSplitter = LineSplitter;
   exports.StringConversionSink = StringConversionSink;
   exports.ClosableStringSink = ClosableStringSink;
   exports.UNICODE_REPLACEMENT_CHARACTER_RUNE = UNICODE_REPLACEMENT_CHARACTER_RUNE;
   exports.UNICODE_BOM_CHARACTER_RUNE = UNICODE_BOM_CHARACTER_RUNE;
   exports.UTF8 = UTF8;
   exports.Utf8Codec = Utf8Codec;
   exports.Utf8Encoder = Utf8Encoder;
   exports.Utf8Decoder = Utf8Decoder;
 })(convert || (convert = {}));