基于 JVM 的編程語言:Coteline
Coteline 是一個全新的基于 JVM 的編程語言。Coteline 是 Ceylon 的超集,并保持對 Ceylon 的向后兼容。
比 Ceylon 改進的地方包括:
-
"
publicas a service", becausesharedis not a good keyword. -
implements, because it is fancier thansatisfiesand it closes the gap for existing J2EE 1.3 developers. -
Call an
objectasingleton. -
Use
constin lieu ofvalue. -
Write
defas a Hipster-compliant variant offunction. -
Ink
Unitinstead ofvoidin your fine-crafted Coteline definitions. -
contractandtraitcarry more meaning thaninterface(and who cares about the actual formal semantics of these?). -
We think
prayis a better replacement forassert, because this is what you actually do when you write assertions. -
dynamicblocks are better named asunsafeblocks, because they escape the wonderland of static type checks. -
Parametric types with
in / outfor contravariance and covariance are hard to manipulate. This is also way too reminiscent of the C# world. Coteline provides salvation withcovarandcontravar. -
Last but not least, you can also write
foreachloops in Coteline.
示例代碼:
"The classic Hello World program"
public Unit hello(String name = "World") {
const str = "Hello, `` name ``!";
def work() => print(str);
work();
pray(1 == 1);
plop.plop();
foreach (i in {1, 2, 3}) {
print(i);
}
}
singleton plop {
public Unit plop() {
print("Oh Plop!");
}
}
"Run the module `better.ceylon.is.coteline`."
public Unit run(){
if (nonempty args=process.arguments) {
foreach (arg in args) {
hello(arg);
}
}
else {
hello();
}
}