![تويتر \ Andrea Bizzotto 💙 على تويتر: "In Dart/Flutter, you can make it *explicit* when a function can return an error with the Either type from the fpdart package. For example, parsing تويتر \ Andrea Bizzotto 💙 على تويتر: "In Dart/Flutter, you can make it *explicit* when a function can return an error with the Either type from the fpdart package. For example, parsing](https://pbs.twimg.com/media/FZLCdqLXEAElFOg.png)
تويتر \ Andrea Bizzotto 💙 على تويتر: "In Dart/Flutter, you can make it *explicit* when a function can return an error with the Either type from the fpdart package. For example, parsing
![The argument type 'String?' can't be assigned to the parameter type 'String'. · Issue #92792 · flutter/flutter · GitHub The argument type 'String?' can't be assigned to the parameter type 'String'. · Issue #92792 · flutter/flutter · GitHub](https://user-images.githubusercontent.com/62276296/139593358-692af748-80e7-473f-a547-b38abae529f5.png)
The argument type 'String?' can't be assigned to the parameter type 'String'. · Issue #92792 · flutter/flutter · GitHub
![flutter - Error: A value of type 'String?' can't be assigned to a variable of type 'String' - Stack Overflow flutter - Error: A value of type 'String?' can't be assigned to a variable of type 'String' - Stack Overflow](https://i.stack.imgur.com/UvjNz.png)
flutter - Error: A value of type 'String?' can't be assigned to a variable of type 'String' - Stack Overflow
![flutter - Null Related Error - The argument type 'String? Function(String)' can't be assigned to the parameter type 'String? Function(String?)?' - Stack Overflow flutter - Null Related Error - The argument type 'String? Function(String)' can't be assigned to the parameter type 'String? Function(String?)?' - Stack Overflow](https://i.stack.imgur.com/JMYgl.png)
flutter - Null Related Error - The argument type 'String? Function(String)' can't be assigned to the parameter type 'String? Function(String?)?' - Stack Overflow
![flutter - Null Related Error - The argument type 'String? Function(String)' can't be assigned to the parameter type 'String? Function(String?)?' - Stack Overflow flutter - Null Related Error - The argument type 'String? Function(String)' can't be assigned to the parameter type 'String? Function(String?)?' - Stack Overflow](https://i.stack.imgur.com/Gco6Q.png)