Allow conversion of EnsoBigInteger to double #3865
Conversation
JaroslavTulach
added
the
CI: Ready to merge
JaroslavTulach
removed
the
CI: Ready to merge
|
Marcin has noted: "This breaks even the truffle contract"
That's certainly a valid concern, @kustosz. Let's address it in 2bea701 - by checking the code in HostToTypeNode and HostUtil I noticed that Truffle languages may expose any |
engine/runtime/src/main/java/org/enso/interpreter/runtime/callable/function/Function.java
Show resolved
Hide resolved
| @@ -19,6 +20,32 @@ public static long add(long a, long b) { | |||
| return a + b; | |||
| } | |||
|
|
|||
| public static double doubleArrayAverage(double[] arr) { | |||
There was a problem hiding this comment.
The averageOfMixedArrayOverDouble test prepares array of power of 2 with 200 elements. Some of them are Long, some of them are EnsoBigInteger.
However the Java side can request them to be converted to double - useful for example for statistic functions where the precision doesn't matter much.
| return sum / arr.length; | ||
| } | ||
|
|
||
| public static double numberArrayAverage(Number[] arr) { |
There was a problem hiding this comment.
Should one need to distinguish between various Enso Number types, one can accept Number[]. The array would contain 63 Long numbers and the rest would be EnsoBigInteger instances that also extend java.lang.Number.
| var sum = BigInteger.ZERO; | ||
| for (int i = 0; i < arr.length; i++) { | ||
| var n = arr[i] instanceof Long l ? BigInteger.valueOf(l) : | ||
| new BigInteger(arr[i].toString()); |
There was a problem hiding this comment.
If one needs to get the precise value of EnsoBigInteger one can use its toString() method and parse the value back.
Alternative would be to make the number implement Callable<java.math.BigInteger> or something other JDK interface (Supplier, Function, etc.) to provide the internal instance of BigInteger.
|
I think the functionality is ready for your review, gentlemen! I am awaiting your comments. |
JaroslavTulach
added
the
CI: Ready to merge
mergify
bot
deleted the
wip/jtulach/ExposeBigIntegerAsDouble_182962982
branch
|
FYI: There is going to be "official" support for |
| @@ -16,7 +16,7 @@ | |||
| /** Internal wrapper for a {@link BigInteger}. */ | |||
| @ExportLibrary(InteropLibrary.class) | |||
| @ExportLibrary(TypesLibrary.class) | |||
| public final class EnsoBigInteger implements TruffleObject { | |||
| public final class EnsoBigInteger extends Number implements TruffleObject { | |||
There was a problem hiding this comment.
Got a comment from Christian Humer:
Your trick with
EnsoBigInteger extends Numberwill not work on Espresso for example.
I guess we'll have to switch to official BigInteger interop once it is available
Pull Request Description
Make sure any Enso number (including
EnsoBigInteger) can be passed to Java via Truffle interop and used on the Java side.Notes
The problem is that there is no support for
java.math.BigIntegerin Truffle interop (as of GraalVM 22.3). We need some "approximations". There is a special handling for everything that "looks like number" - e.g. extendsjava.lang.Numberin the Truffle interop. Let's use that! That's the reason whyEnsoBigIntegernow extendsNumber.That opens three possibilities on Java side:
java.math.BigIntegerviatoStringas the last test shows - slow, but preciseChecklist
Please include the following checklist in your PR:
Java,
style guides.