First draft of translation document

Brian Goetz brian.goetz at
Thu May 20 08:32:34 PDT 2010

> With regard to the recent proposals, the advantages of interface
> injection are clear. I do not see any clear advantage to MethodHandle
> with bind for partial application (but maybe I'm just missing something)

Yes, you're missing something: optimization!

To take a simple example, lets say I have a function

   f(x, y) { if (x != null) else }

If I partially apply x, now x is a constant for purposes of compilation.  So 
if I partially apply a null x argument, the test and branch get 
dead-code-eliminated and it reduces to

   f(y) { }

This may not seem like a big deal, but partial application gives the VM way 
more information -- type information, nullity information, array bounds 
information -- with which it can perform all sorts of optimizations (type 
sharpening which leads to better inlining, null check elimination, array 
bounds check elimination, dead code elimination, etc).

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