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Comment by simula67 | Hacker News Reader

> I think folks using and learning .NET should have the same experience as with Go or Ruby. > Easy Compile and Run > Just "dotnet run" and it compiles AND executes

As someone who does not follow the .NET landscape that closely can anyone explain why this is a big deal ? Java has been able to do 'javac Hello.java; java Hello' for as long as I can remember. If this was so important why are they getting around to it only now ?

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Your story (javac / java) was supported since day 1. You had a compiler (say, mcs or csc) that you could invoke manually, passing the input files (csc Hello.cs) and could run the result (either via 'mono Hello.exe' or just 'Hello.exe').

This is more like maven or leiningen I guess - you can build and run, manage dependencies, create projects. That said, I'm not up to date in the Java landscape.

If java did the same it would be "java Hello" regardless of whether it was built or not. It would compile and run, or just run if it was already compiled. Not sure why that is a big deal but I do think the separation between jre and sdk in java is mostly a headache. I understand the end user doesn't need all the docs etc., but shipping the compiler with the runtime, why not?

It is been done for years by third party JVM vendors, but apparently many are too focused on the OpenJDK.

Also, since Java 8 you can package everything together with the reference JDK, no need for third party tools any longer. This will be improved with the Java 9 modularity and possible AOT compilation in Java 10.

Do you actually use Java like this on any non-trivial project?

This is intended to be a high-level tool that can be used as an alternative to IDEs.

Learning the tooling is a very hard barrier to entry. Not that it's difficult per se, but a lot of people will try something to "see how it is", and being able to just get it to run, right now, no multiple command no nothing, that let them concentrate on the interesting parts.

Yes, for simple 'Hello World' in one class file it is not big deal. But 'java/javac' is very clumsy and insufficient for big project with large number of class files and dependency jars. I hope 'dotnet' will be more sophisticated.

This is more along the lines of gcj than javac.

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