Better integration of floating-point values

moor/lib/src/dsl/columns.dart

@@ -28,7 +28,8 @@ abstract class DateTimeColumn extends Column<DateTime, DateTimeType> {}
 abstract class BlobColumn extends Column<Uint8List, BlobType> {}
 
 /// A column that stores floating point numeric values.
-abstract class RealColumn extends Column<num, RealType> {}
+abstract class RealColumn extends Column<double, RealType>
+    implements DoubleExpression {}
 
 /// A column builder is used to specify which columns should appear in a table.
 /// All of the methods defined in this class and its subclasses are not meant to

moor/lib/src/runtime/expressions/comparable.dart

@@ -2,7 +2,10 @@ import 'package:moor/moor.dart';
 import 'expression.dart';
 
 abstract class IntExpression extends Expression<int, IntType>
-    with ComparableExpr {}
+    implements ComparableExpr<int, IntType> {}
+
+abstract class DoubleExpression extends Expression<double, RealType>
+    implements ComparableExpr<double, RealType> {}
 
 mixin ComparableExpr<DT, ST extends SqlType<DT>> on Expression<DT, ST> {
   /// Returns an expression that is true if this expression is strictly bigger

moor/lib/src/runtime/expressions/variables.dart

@@ -37,7 +37,7 @@ class Variable<T, S extends SqlType<T>> extends Expression<T, S> {
   }
 
   /// Creates a variable that holds the specified floating point value.
-  static Variable<num, RealType> withReal(num value) {
+  static Variable<double, RealType> withReal(double value) {
     return Variable(value);
   }
 

moor/lib/src/runtime/structure/columns.dart

@@ -193,18 +193,25 @@ class GeneratedDateTimeColumn extends GeneratedColumn<DateTime, DateTimeType>
 class GeneratedBlobColumn extends GeneratedColumn<Uint8List, BlobType>
     implements BlobColumn {
   GeneratedBlobColumn(String $name, String tableName, bool $nullable,
-      {String $customConstraints})
+      {String $customConstraints, Expression<Uint8List, BlobType> defaultValue})
       : super($name, tableName, $nullable,
-            $customConstraints: $customConstraints);
+            $customConstraints: $customConstraints, defaultValue: defaultValue);
 
   @override
   final String typeName = 'BLOB';
 }
 
-class GeneratedRealColumn extends GeneratedColumn<num, RealType>
+class GeneratedRealColumn extends GeneratedColumn<double, RealType>
+    with ComparableExpr
     implements RealColumn {
-  GeneratedRealColumn(String $name, String tableName, bool $nullable)
+  GeneratedRealColumn(
-      : super($name, tableName, $nullable);
+    String $name,
+    String tableName,
+    bool $nullable, {
+    Expression<double, RealType> defaultValue,
+    String $customConstraints,
+  }) : super($name, tableName, $nullable,
+            defaultValue: defaultValue, $customConstraints: $customConstraints);
 
   @override
   String get typeName => 'REAL';

moor/lib/src/types/sql_types.dart

@@ -112,11 +112,11 @@ class BlobType extends SqlType<Uint8List> {
   mapToSqlVariable(content) => content;
 }
 
-class RealType extends SqlType<num> {
+class RealType extends SqlType<double> {
   const RealType();
 
   @override
-  num mapFromDatabaseResponse(response) => response as num;
+  double mapFromDatabaseResponse(response) => (response as num).toDouble();
 
   @override
   String mapToSqlConstant(num content) => content.toString();

moor/test/data/tables/todos.g.dart

@@ -625,26 +625,26 @@ class $SharedTodosTable extends SharedTodos
 
 class TableWithoutPKData extends DataClass {
   final int notReallyAnId;
-  final num someFloat;
+  final double someFloat;
   TableWithoutPKData({this.notReallyAnId, this.someFloat});
   factory TableWithoutPKData.fromData(
       Map<String, dynamic> data, GeneratedDatabase db,
       {String prefix}) {
     final effectivePrefix = prefix ?? '';
     final intType = db.typeSystem.forDartType<int>();
-    final numType = db.typeSystem.forDartType<num>();
+    final doubleType = db.typeSystem.forDartType<double>();
     return TableWithoutPKData(
       notReallyAnId: intType
           .mapFromDatabaseResponse(data['${effectivePrefix}not_really_an_id']),
-      someFloat:
+      someFloat: doubleType
-          numType.mapFromDatabaseResponse(data['${effectivePrefix}some_float']),
+          .mapFromDatabaseResponse(data['${effectivePrefix}some_float']),
     );
   }
   factory TableWithoutPKData.fromJson(Map<String, dynamic> json,
       {ValueSerializer serializer = const ValueSerializer.defaults()}) {
     return TableWithoutPKData(
       notReallyAnId: serializer.fromJson<int>(json['notReallyAnId']),
-      someFloat: serializer.fromJson<num>(json['someFloat']),
+      someFloat: serializer.fromJson<double>(json['someFloat']),
     );
   }
   @override
@@ -652,11 +652,11 @@ class TableWithoutPKData extends DataClass {
       {ValueSerializer serializer = const ValueSerializer.defaults()}) {
     return {
       'notReallyAnId': serializer.toJson<int>(notReallyAnId),
-      'someFloat': serializer.toJson<num>(someFloat),
+      'someFloat': serializer.toJson<double>(someFloat),
     };
   }
 
-  TableWithoutPKData copyWith({int notReallyAnId, num someFloat}) =>
+  TableWithoutPKData copyWith({int notReallyAnId, double someFloat}) =>
       TableWithoutPKData(
         notReallyAnId: notReallyAnId ?? this.notReallyAnId,
         someFloat: someFloat ?? this.someFloat,
@@ -737,7 +737,7 @@ class $TableWithoutPKTable extends TableWithoutPK
       map['not_really_an_id'] = Variable<int, IntType>(d.notReallyAnId);
     }
     if (d.someFloat != null || includeNulls) {
-      map['some_float'] = Variable<num, RealType>(d.someFloat);
+      map['some_float'] = Variable<double, RealType>(d.someFloat);
     }
     return map;
   }

moor/test/insert_test.dart

@@ -24,6 +24,18 @@ void main() {
         ['Implement insert statements']));
   });
 
+  test('can insert floating point values', () async {
+    // regression test for https://github.com/simolus3/moor/issues/30
+    await db
+        .into(db.tableWithoutPK)
+        .insert(TableWithoutPKData(notReallyAnId: 42, someFloat: 3.1415));
+
+    verify(executor.runInsert(
+        'INSERT INTO table_without_p_k '
+        '(not_really_an_id, some_float) VALUES (?, ?)',
+        [42, 3.1415]));
+  });
+
   test('generates insert or replace statements', () async {
     await db.into(db.todosTable).insert(
         TodoEntry(

moor_generator/lib/src/model/specified_column.dart

@@ -76,7 +76,7 @@ class SpecifiedColumn {
         ColumnType.integer: 'int',
         ColumnType.datetime: 'DateTime',
         ColumnType.blob: 'Uint8List',
-        ColumnType.real: 'num',
+        ColumnType.real: 'double',
       }[type];
 
   /// The column type from the dsl library. For instance, if a table has