A good way to show errors to the user

[croqaz]

The original issue is at: ShinyTrinkets/twofold.js#3

Some TwoFold tags will have errors and the user wants to see them.
The errors will be logged in the STDOUT of the command line app, but it's not cool to let the user switch to the terminal to see the errors, especially if the error happened some time ago...

The solution should be implemented at framework level - but the tags are free to implement their own error mechanism, to return the error message, instead of the success text, because the framework doesn't care.

Possible solutions:

• write the error in the same place where the the success text would be written?
  con: the user needs to delete the ugly error text, manually, which triggers another render, which injects the error text again if the error still happens
• write the error in a prop inside the tag. Eg: <someTag error="Ooops!" />.
• create a new tag maybe called <err></err> and dump the most recent X errors in there?
  con: the user needs to know about this tag and remember to use it! If the tag errors for some reason, the user might think the app is not working, because it's not responding to their input.

Any other ideas 💡 ?