Proof of concept: wrapper extension for widget

main.dart

import 'package:flutter/material.dart';

extension Wrapper on Widget {
  Widget wrap(List<Function> wrappers) {
    var next = this;

    for (var i = wrappers.length - 1; i >= 0; i--) {
      next = wrappers[i](next);
    }

    return next;
  }
}

void main() {
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        primarySwatch: Colors.blue,
        visualDensity: VisualDensity.adaptivePlatformDensity,
      ),
      home: MyHomePage(title: 'Flutter Demo Home Page'),
    );
  }
}

class MyHomePage extends StatefulWidget {
  MyHomePage({Key key, this.title}) : super(key: key);

  final String title;

  @override
  _MyHomePageState createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  double _counter = 0;

  void _incrementCounter() {
    setState(() {
      _counter++;
    });
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text(widget.title),
      ),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            Text(
              'You have pushed the button this many times:',
            ),
            Text(
              '$_counter',
              style: Theme.of(context).textTheme.headline4,
            ).wrap([
              (next) => GestureDetector(
                    onTap: () {
                      print('hai');
                      setState(() {
                        _counter++;
                      });
                    },
                    child: next,
                  ),
              (next) => Container(
                    padding: EdgeInsets.all(_counter),
                    decoration: BoxDecoration(
                      border: Border.all(width: 1, color: Colors.black),
                    ),
                    child: next,
                  ),
            ]),
          ],
        ),
      ),
      floatingActionButton: FloatingActionButton(
        onPressed: _incrementCounter,
        tooltip: 'Increment',
        child: Icon(Icons.add),
      ),
    );
  }
}

Another variant with fold

Widget wrap(List<Function> wrappers) {
  return wrappers.reversed.fold(this, (next, wrapper) => wrapper(next));
}

Naming is hard!

extension Modifier on Widget {
  Widget modify(List<Function> modifiers) {
    return modifiers.reversed.fold(this, (next, modifier) => modifier(next));
  }
}