From Greg Weber, Fri Mar 23 14:24:24 CET 2012:
This proposal doesn't have to break any codebases.
One possibility is to add the Text type to the standard while keeping String and marking it as deprecated.

I for one would like to go on the record as being against any notion of "deprecating" String.

Text is good for many use-cases, but it has very different asymptotic behavior for many operations, and cannot serve as a one-size-fits-all replacement for String.

I am less strongly against adding Text to the standard, but mostly because I am leery in that it brings a lot of language specification baggage and risks making attempts to explore the design space around Text harder. (e.g. Jasper's GSoC project this last year to investigate using UTF-8 encoded Data.Text would have been a much harder sell if Text was codified in the language standard!)

Text has a remarkably (necessarily) large API and for the first time, as far as I can see, the specification would be largely requiring users to use qualified imports to access everything inside of it, which complicates the language standard from a pedagogical standpoint.

Isn't it enough that it is part of the platform?

-Edward