[data] add Render instance for Record (#1008) #1019
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| val insts = RecordInternal.summonRender[ev.Names, ev.Values] | ||
| Render.instance: (value: Record[Fields]) => | ||
| value.toMap.map((field, value) => | ||
| insts(field.name) match |
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Will insts always contain all values as the map? Is apply safe here?
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It's not safe and there was a bug here because of record subtyping (we may want to print rich record as record with only one field)
I have fixed that and added test
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I was about to post a PR generalizing |
| builder.toString() | ||
| end asText | ||
| end new | ||
| Render.instance: (value: A) => |
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Do we need Render.instance? I think the compiler can materialize Render directly from an anonymous function
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When I try to to make Render in inline methods via anonymous function I get compiler warn:
An inline given alias with a function value as right-hand side can significantly increase
generated code size. You should either drop the `inline` or rewrite the given with an
explicit `apply` method.
May be we can just ignore this warn, not sure.
The main reason I've added I think your approach is much better and So, let's finish your PR first, and after that I will fix this PR. |
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Cool! I've just posted #1021 |
[data] make `~` an abstract type
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| @@ -432,10 +432,12 @@ class RecordTest extends Test: | |||
| """) | |||
| } | |||
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| "not compile when fields lack CanEqual" in { | |||
| "not compile when fields lack CanEqual" in pendingUntilFixed { // looks like scala3 bug | |||
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I don't know why this test works in main
When I was fighting with it, I minimized my case to
import scala.compiletime.*
import scala.language.strictEquality
class Lol
object Lol:
inline given CanEqual[Lol, Lol] = error("lol")
val x = new Lol
val y = new Lol
// summon[CanEqual[Lol, Lol]] // doesn't compile
x == y // compile, and this is strangehttps://scastie.scala-lang.org/road21/B8hWnSQNTriBcOYndUduRg
For me this looks like a bug in scala3 compiler, what do you think?
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yeah, that's odd. I can follow up on this
I had to extend
FieldsLikeevidence to deriveRenderinstances, and now it also contains tuples (types) of names and values.Also I have noticed that an actual type of
~is never used, so I removed it and now~is an abstract type member.