Make errorMessage write to stderr

[sras]

No description provided.

[chshersh]

Hi @sras, thanks for your interest in colourista. Before going directly to the implementation, I would like to tell vision about the subject.

The fact that you print something to stderr doesn't mean that it is an error. The name of the stderr is unfortunate. Still, one of the main usages for stderr is to print some debugging or logging information in there, so you can safely pipe the output of your tools to other CLI consumers without the need for them to handle diverse format of all logging messages. In this context, making only errorMessage print to stderr and not other functions seems a bit inconsistent with the general idea.

I don't mind introducing new functions like formattedMessageStderr and formattedMessageHandle to give more flexibility to users. But regarding output handle for all functions — this requires some thinking and discussions. @vrom911 and I were thinking about possible solutions for this problem and how to give more flexibility to users by providing the consistent interface at the same time. I guess, the latter issue will take some time, but two helpful functions (which I mentioned above) can be added to the library meanwhile 🙂