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Noscript is an object-oriented, class-less language running on the Rubinius VM.
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Readme.md

noscript

Noscript is an object-oriented, class-less programming language running on the Rubinius Virtual Machine.

It takes design ideas from JavaScript, CoffeeScript, Self, IO and our beloved Ruby.

Installing

Noscript only runs on Rubinius, so you have to install it (if you use RVM, here is how you do it). Assuming you have it installed:

rvm use rbx-head
git clone git://github.com/txus/noscript.git
cd noscript

You can run your programs like this, pretty standard:

./bin/noscript examples/objects.ns

Or execute arbitrary code:

./bin/noscript -e "123.inspect().print()"

Use the -A and -B to show the AST representation and the generated Rubinius bytecode if you want. Fun! :)

Object Model

Noscript is prototype-based. Every object is a clone of another object with a reference to it. An object is just a collection of slots that can be assigned and retrieved. These slots can contain anything: literals, functions and other objects.

As a difference with most languages, identifiers may contain whitespace. So foo, each pair and do something awesome are all valid identifiers for local variables, object attributes or method names. Due to this, function invocations or method calls must have parens: do something awesome returns a function, whereas do something awesome() calls it. Just like JavaScript.

Object is the master object to clone from, available from the main scope.

To create your first object, type this:

greeter = Object.clone()
greeter.salute = -> name
  ("Hello %s!" % name).puts()
end
greeter.salute()

Basic data types

  • [1, 2, 3]: Arrays. Iterable through #each.
  • {a: 3, b: 9}: Tuples. Iterable through #each pair.
  • 1: Fixnums. Duh.
  • '1': Strings. You can format them: 'Hello %s' % 'world'.
  • -> arg1, argN; foo(); end: Function literals.

Behavior reusability through Traits

Traits are like Ruby modules in the sense that they can be used to define composable units of behavior, but they are not included hierarchically. They are truly composable, meaning that are pieces that must either fit perfectly or the host object must provide a way for them to do it, normally resolving conflicts by explicitly redefining the conflicting methods.

Create your first trait like this:

Runnable = Trait.build("Runnable", {
  run: ->
    "Running!".puts()
  end
})

Serious = Trait.build("Serious", {
  run: ->
    "Running a serious business.".puts()
  end
})

person = Object.clone()
person.age = 20
person.uses(Runnable)

# If we did this now, Noscript would raise a trait conflict error, because
# person cannot have two traits with methods with the same names:
#
# person.uses(Serious)
#
# Instead we have to resolve the conflict defining the #run method on the host.

person.run = ->
  if @age > 30
    @Serious run()
  else
    @Runnable run()
  end
end

person.uses(Serious)

person.run()
# => Outputs "Running!"
person.age = 35
person.run()
# => Outputs "Running a serious business."

To read more about how traits work, read examples/traits.ns.

Installing the old interpreter (AST-walker)

Before running on the Rubinius VM, Noscript was prototyped as a simple AST-walker interpreter written in pure Ruby, without any Rubinius-specific code.

If you want to check out what it was before I started the rewrite, check out the branch named "old".

The old branch is far from usable, but it's a nice example to play with.

git clone git://github.com/txus/noscript
git checkout old
cd noscript
bundle install
./bin/noscript examples/hello_world.ns
./bin/noscript examples/interop.ns
./bin/noscript examples/objects.ns
./bin/noscript examples/test_case.ns
./bin/noscript examples/traits.ns

Who's this

This was made by Josep M. Bach (Txus) under the MIT license. I'm @txustice on twitter (where you should probably follow me!).

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