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I don't remember anymore what's the best/right way to convert a Node.js `Buffer` to a Kotlin `ByteAr...
# javascript
e
I don't remember anymore what's the best/right way to convert a Node.js 
Buffer
to a Kotlin 
ByteArray
v
I guess 
buffer._asList_()._toByteArray_()
, but I have no idea actually. 🙂
e
I'd expect 
.unsafeCast<ByteArray>()
to work, but actually since 
Buffer
extends 
UInt8Array
and not 
Int8Array
it might have weird behavior without wrapping… haven't tested
(e.g. 
Int8Array(buffer).unsafeCast<ByteArray>()
)
t
Draft (from gist)
Copy code
val uint8 = Uint8Array(arrayOf(1,2))

// conversion
val int8 = Int8Array(uint8.buffer)
val ba = int8.asByteArray()
asByteArray()
extension - fine PR :)
e
@turansky depends if the byte representation changes with
Copy code
Int8Array(uint8.buffer)
Would 
asByteArray
simply 
unsafeCast
?
t
Would 
asByteArray
simply 
unsafeCast
?
Yes
e
gratitude thank you 1
e
Byte representation seems to remain the same. So it would be a matter of adding 
asByteArray
e
Uint8ClampedArray
will clamp values outside of range, as its name implies, other JS TypedArray types will reinterpret the bits
e
will reinterpret the bits
As a "view" over those bits tho, right? If you transform a 
Int8Array
to a 
UInt8Array
you get back the correct result
e
yes, and ditto if you go through 
Int32Array
etc. too (assuming you have a correct multiple number of bytes)
v
Btw. is there anything bad with my suggestion?
e
copy
v
swimmingpool
e
@Vampire I guess I don't really like the additional 
buffer._asList_()
But that's it, nothing wrong with it
e
.toByteArray
makes a copy while the 
*TypedArray
constructors and 
unsafeCast
don't
e
Well, apart from the copying every single byte
e
whether that matters is situational of course, but if you're using 
Buffer
to begin with…
✔️ 1
v
Ah, I see, thx
t
@Edoardo Luppi What is your use case? Do you need 
ByteArray
for Kotlin library? cc @Sergei Grishchenko
e
@turansky sorry didn't get pinged. I need to expose a 
ByteArray
in common code, thus I need to convert the JS 
Buffer
to said 
ByteArray
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