4 ms·

Scala is one of those great languages with that one Achilles heel. The speed of that compiler: $ time scalac Hello.scala real 0m2,907s user 0m7

Scala is one of those great languages with that one Achilles heel. The speed of that compiler: $ time scalac Hello.scala real 0m2,907s user 0m7,901s sys 0m0,308s $ cat Hello.scala object Hello{ def main(args: Array[String]){ println("hello world") } } Implicit type conversion can be debated I guess, but otherwise a very beautiful language.

lihaoyi 6y ago
Yeah cold compiles are slow, but most modern tools keep a hot compiler to re-use and once warm a hot compile of hello world is more like ~200ms. There's a bit of complexity managing these daemons, but that's something that the build tool normaly handles for you transparently
- bjarneh 6y ago
  Yes it gets better, and the 'fsc' (Fast Scala Compiler) does improve on the situation somewhat; but I've always found it annoyingly slow. It should be mentioned that I haven't looked very hard at that language in many years for that very reason; so things could have improved somewhat. And from what I understand, the next version of Scala (Dotty) is going address this issue (build speed).
  - lihaoyi 6y ago
    The compiler has sped up 3x in the past few years. That's a very big speedup, and the current experience is likely nothing like what you remember
    - bjarneh 6y ago
      Sounds good, perhaps a language that needs a revisit.
_a1_ 6y ago
Using scalac is not a standard use case. Standard use case is to use sbt (well, or mill, since we're in lihaoyi's thread :D). Sbt starts up slow, but with bloop, or sbtn (native client of sbt), the compilation is really fast (much faster than C++ for example): $ time sbtc compile [info] entering *experimental* thin client - BEEP WHIRR [info] terminate the server with `shutdown` > compile [info] compiling 1 Scala source to /home/.../target/scala-2.13/classes ... [info] compile completed [success] Total time: 0 s, completed Feb 11, 2021 4:21:51 PM sbtc compile 0,08s user 0,02s system 21% cpu 0,492 total
- thinkharderdev 6y ago
  Yeah, set 1.4 was a huge improvement. I wrote a lot of scala several years ago and just got back into it this year and the dev experience is much nicer now with the SBT sever model

lihaoyi 6y ago

Yeah cold compiles are slow, but most modern tools keep a hot compiler to re-use and once warm a hot compile of hello world is more like ~200ms. There's a bit of complexity managing these daemons, but that's something that the build tool normaly handles for you transparently

bjarneh 6y ago
Yes it gets better, and the 'fsc' (Fast Scala Compiler) does improve on the situation somewhat; but I've always found it annoyingly slow. It should be mentioned that I haven't looked very hard at that language in many years for that very reason; so things could have improved somewhat. And from what I understand, the next version of Scala (Dotty) is going address this issue (build speed).
- lihaoyi 6y ago
  The compiler has sped up 3x in the past few years. That's a very big speedup, and the current experience is likely nothing like what you remember
  - bjarneh 6y ago
    Sounds good, perhaps a language that needs a revisit.

_a1_ 6y ago

Using scalac is not a standard use case. Standard use case is to use sbt (well, or mill, since we're in lihaoyi's thread :D). Sbt starts up slow, but with bloop, or sbtn (native client of sbt), the compilation is really fast (much faster than C++ for example): $ time sbtc compile [info] entering *experimental* thin client - BEEP WHIRR [info] terminate the server with `shutdown` > compile [info] compiling 1 Scala source to /home/.../target/scala-2.13/classes ... [info] compile completed [success] Total time: 0 s, completed Feb 11, 2021 4:21:51 PM sbtc compile 0,08s user 0,02s system 21% cpu 0,492 total

thinkharderdev 6y ago
Yeah, set 1.4 was a huge improvement. I wrote a lot of scala several years ago and just got back into it this year and the dev experience is much nicer now with the SBT sever model