I want to execute a following script using Scala3:
@main def m() =
println("Hello, world! I'm a script")
When I type the command, scala hello.scala, I get the following error:
/Users/avirals/dev/learning-scala/hello-world/hello.scala:1: error: not found: type main
@main def m() =
^
one error found
I think it is because I have both the versions of Scala installed (2 and 3). I know how to start a REPL for both (as mentioned here) but I am not able to execute a Scala3 script from the command line.
[Update]
I tried scala3-repl hello.scala and it just opens the REPL:
➜ learning-scala git:(main) scala3-repl hello.scala
scala> m()
1 |m()
|^
|Not found: m
How do I execute a Scala 3 script from the command line given I have two different versions (2 and 3) of Scala installed?
My OS: MacOS
Update 2
As suggested in this answer, I tried running with amm and it worked for a few scripts. However, the following script failed:
Script:
@main def m(args: String*) =
var i = 0
while i < args.length do
println(args(i))
i += 1
Error:
➜ learning-scala git:(main) amm printargs.scala
printargs.scala:2:3 expected (If | While | Try | DoWhile | For | Throw | Return | ImplicitLambda | SmallerExprOrLambda)
var i = 0
^
Running the above script in a Scala3-REPL works:
➜ learning-scala git:(main) scala3-repl
scala> @main def m(args: String*) =
| var i = 0
| while i < args.length do
| println(args(i))
| i += 1
|
def m(args: String*): Unit
scala> m("aviral", "srivastava")
aviral
srivastava
Running the same script in a system (MacOS) that has only Scala3 installed works just fine as well.
