Spago doesn't tell what is a warning and what is an error

[flip111]

A warning

[395/395 UnusedName] src/Websocket.purs:377:7

  377        otherwise      -> pure unit
             ^^^^^^^^^

  Name otherwise was introduced but not used.
  in value declaration receiveServerEvent

An error

[2/2 UnknownImport] src/Websocket.purs:39:26

  39  import Data.Array.Extra (firstMaybe)
                               ^^^^^^^^^^

  Cannot import value firstMaybe from module Data.Array.Extra
  It either does not exist or the module does not export it.

The only way to tell that it is a warning or an error is by the color. But now we immediately see the problem, as soon as you copy paste and lose terminal colors the information is gone. I would suggest the following:
395 Warning UnusedName in src/Websocket.purs:377:7

The /395 and the brackets [, ] don't really add much but i would be ok if they stayed

[f-f]

Ah indeed - the output of the compiler is going through PSA, so I think we should be able to patch it there? (cc @JordanMartinez)

[JordanMartinez]

Yeah, this part would need to be updated if one wanted to add support for this: https://github.com/purescript/spago/blob/master/src/Spago/Psa/Printer.purs#L73-L90. I don't personally see the need, so I'm not interested in implementing that.