REPL uses CPU while doing nothing

[borkdude]

Description

I have tried the eta-scotty-example https://github.com/Jyothsnasrinivas/eta-scotty-example in the etlas repl.
When the REPL is showing a prompt and not doing anything else, the CPU usage for a java process goes up to 150% on my Macbook Air.

Expected Behavior

I expect the REPL to not use much resources when idling.

Actual Behavior

150% CPU usage on a Macbook Air.

Steps to Reproduce

1. git clone https://github.com/Jyothsnasrinivas/eta-scotty-example
2. cd eta-scotty-example
3. etlas repl
4. wait for the prompt

Your Environment

• Current Eta & Etlas version:

etlas version 1.5.0.0
compiled using version 2.1.0.0 of the etlas-cabal library
Eta REPL v0.8.6b1

java version "1.8.0_45"
Java(TM) SE Runtime Environment (build 1.8.0_45-b14)
Java HotSpot(TM) 64-Bit Server VM (build 25.45-b02, mixed mode)

• Operating System and version:
  MacOS El Capitan 10.11.6

[rahulmutt]

This is a duplicate of #839. This will be fixed in 0.8.6b2 which will be released within the next week.