On 20/10/15 19:35, Gregory Collins wrote:
On Tue, Oct 20, 2015 at 7:45 AM, Jeremy <voldermort@hotmail.com> wrote:
I'm interested in why you think recent changes are making Haskell a less
viable alternative to mainstream languages.

[...] Of course, these hypothetical productivity benefits are extremely difficult to quantify (and Lord knows, we've tried), but that's not at all true for the "con" arguments:
  • how many Haskell programmers are there in industry? If I lose my local expert who is trying to push us to use this thing, can I hire another?
  • how many lines of code are written in Haskell globally vs other languages?
  • how much tooling will I have available to help me if I choose Haskell vs. a "safer" technology like Java, Python, or Go?
  • how many open source libraries will I have available to me to handle common tasks, and what is their quality?
  • how likely am I to encounter bugs in the compiler or base libraries?
We actually get these questions from potential clients *all the time* (in particular, everyone asks 1 and 3). I don't always have a convincing answer.
The point Johan is trying to make is this: if I'm thinking of using Haskell, then I'm taking on a lot of project risk to get a (hypothetical, difficult to quantify) X% productivity benefit. If choosing it actually costs me a (real, obvious, easy to quantify) Y% tax because I have to invest K hours every other quarter fixing all my programs to cope with random/spurious changes in the ecosystem and base libraries, then unless we can clearly convince people that X >> Y, the rationale for choosing to use it is degraded or even nullified altogether.
Not even that. Learning and some tooling costs can be amortized over time, but a regular and frequent cost tied to upgrades in the ecosystem may be really hard to estimate in advance. This makes profit, viability and deadlines, mid-term and long-term, really hard to estimate and fulfill. (I've also tried, and often failed.)

If clients (supervisors, project managers, <your company>) have *any* doubts that using the language may be cost-effective, they won't go for it.

Cheers

Ivan