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##### Activity
• May 23 10:17
scala-impala starred fthomas/refined
• May 22 04:03
• May 19 15:41
jackyevo938 starred fthomas/refined
• May 19 10:18
jelmerk starred fthomas/refined
• May 18 07:38
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• May 18 05:54
daofaziran1 starred fthomas/refined
• May 17 22:48
armanbilge commented #932
• May 17 22:08
note commented #932
• May 17 22:08
note commented #932
• May 17 22:07
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• May 17 22:05
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• May 17 22:02
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• May 17 17:40
• May 17 02:38
Kensuke-Hinata starred fthomas/refined
• May 17 02:36
uazw starred fthomas/refined
• May 16 15:15
armanbilge commented #932
• May 16 14:47
gcnyin starred fthomas/refined
• May 16 13:30
armanbilge commented #932
• May 14 01:24
codecov[bot] commented #1086
• May 14 01:24
codecov[bot] commented #1086
Raúl Piaggio
@rpiaggio
ok, it seems to work with type UpperNEString = String Refined And[NonEmpty, Forall[UpperCase]]. Thank you very much!
Andrii
@aaabramov

Hi all!

I've learned BigDecimal support in fthomas/refined#345 & fthomas/refined#36
But I am unable to create RefinedTypeOps for BigDecimal with Closed predicate.
I would like to achieve something like

  type Percent = Refined[BigDecimal, Closed[W.0.0.T, W.100.0.T]]
object Percent extends RefinedTypeOps[Percent, BigDecimal]

// What I've tried:
type Percent = Refined[BigDecimal, Closed[W.BigDecimal(0.0).T, W.BigDecimal(100.0).T]]
object Percent extends RefinedTypeOps[Percent, BigDecimal]

type Percent = Refined[BigDecimal, Closed[W.BigDecimal("0.0").T, W.BigDecimal("100.0").T]]
object Percent extends RefinedTypeOps[Percent, BigDecimal]
And, of course, I am getting
could not find implicit value for parameter rt: eu.timepit.refined.api.RefinedType.AuxT[com.xxx.Percent,BigDecimal]
[error]   object Percent extends RefinedTypeOps[Percent, BigDecimal]
Leif Warner
@LeifW
Anyone have an opinion on which would be better (lower runtime cost, hopefully) between refined Size vs shapeless Sized?
Just thinking to assert e.g. a byte array has 8 elements (so I know it can represent a Long).
Dmytro Mitin
@DmytroMitin
Aleksei Shamenev
@coffius

Hi there 🙋‍♂️
I wonder if it is possible to check that one int is less than or equal to another int.
Using refined + literal-based singleton types from SIP-23
Something like that:

trait <=[MIN, MAX] {} // Should be automagically derived during compilation
// Only if MIN <= MAX

class GenericStringValidator[MIN: ValueOf, MAX: ValueOf](implicit ev: MIN <= MAX) {
private val minValue = implicitly[ValueOf[MIN]].value
private val maxValue = implicitly[ValueOf[MAX]].value
}

P.S.: That piece of code in scastie

Aleksei Shamenev
@coffius
SOLVED 👆
Accidently scrolled up to the message and found the answer. Thanks, chat 😊
Oron Port
@soronpo
@coffius just a tip. From my experience it's better to have classes unconstrained with private construcor and constrained with a public definition in a companion.
Aleksei Shamenev
@coffius
@soronpo, Hmm... Interesting idea. But maybe you can elaborate it a little bit more. I am not sure if I understand it good enough.
Oron Port
@soronpo

@coffius
With your example I would have done:

class GenericStringValidator private [Min <: Int, Max <: Int](minValue : Min, maxValue : Max) {
}
object GenericStringValidator  {
def apply[Min <: Int with Singleton, Max <: Int with Singleton](min : Min, max : Max)(implicit  r : Require[Min <= Max]) = new GenericStringValidator(min, max)
}

If you have further questions it's better to ask in the singleton-ops gitter

Aleksei Shamenev
@coffius
@soronpo, Ok, now I got it. No further questions. Thanks 🙇‍♂️
matrixbot
@matrixbot
@jarek_rozanski:matrix.org I was wondering if it possible to apply Refined types to key and value of a Map
Jarek Rozanski
@jrozanski
Apologies for clunky Matrix bot earlier. In essence I am trying to apply Refined to a generic Map, and defining refined type to Keys and Values. Imagine something along the lines of:
type ValidMap = Map[String Refined NonEmpty, Long Refined Closed[W.0.T, W.100,T]
Jens Grassel
@jan0sch
@jrozanski It should work, I've something like this:
type FormField = String Refined (Trimmed And NonEmpty)
type ErrorMessage = String Refined NonEmpty
type FormErrors = Map[FormField, List[ErrorMessage]]
However you'll need to construct our instances via Map or write an object ValidMap with the appropriate helper functions.
David Strawn
@isomarcte
Is there current work underway for supporting something analogous to RefineMacro in Scala 3.x.x?
fthomas
@fthomas:matrix.org
[m]
@isomarcte: I'm not working on a RefineMacro equivalent for Scala 3 right now. My current understanding is that it is not possible to have something similar in Scala 3. But I've not played a lot with Scala 3 yet, so maybe there is a way to have this functionality and I'm not aware of it.
Denis Novac
@DenisNovac

Hi everyone. I am trying to make this string restrictions:

prefix: String Refined PrefixConstraints
type PrefixConstraints = NonEmpty And Not[Contains['.']] And Forall[LowerCase] And Head[Letter]

But i am getting errors with strings like "t-m" because of dash:

[error] java.lang.Error: ConvertFailure(CannotConvert("t-m",eu.timepit.refined.api.Refined[String,eu.timepit.refined.boolean.And[eu.timepit.refined.boolean.And[eu.timepit.refined.boolean.And[eu.timepit.refined.boolean.Not[eu.timepit.refined.collection.Empty],eu.timepit.refined.boolean.Not[eu.timepit.refined.boolean.Not[eu.timepit.refined.collection.Forall[eu.timepit.refined.boolean.Not[eu.timepit.refined.generic.Equal[Char('.')]]]]]],eu.timepit.refined.collection.Forall[eu.timepit.refined.char.LowerCase]],eu.timepit.refined.collection.Head[eu.timepit.refined.char.Letter]]],Left predicate of (((!isEmpty(t-m) && !!(!(t == .) && !(- == .) && !(m == .))) && (isLower('t') && isLower('-') && isLower('m'))) && isLetter('t')) failed: Right predicate of ((!isEmpty(t-m) && !!(!(t == .) && !(- == .) && !(m == .))) && (isLower('t') && isLower('-') && isLower('m'))) failed: Predicate failed: (isLower('t') && isLower('-') && isLower('m')).),

This is happens because of Forall[LowerCase]. It seems that it is also restrict my string to only chars. Is there a workaround for this? I want to have numbers or dashes in my string with only lowercased chars.

Zhenhao Li
@Zhen-hao
hi, is there a version of applyRef that gives a ValidatedNel instead of Either
Zhenhao Li
@Zhen-hao
so for type A = String Refined P1 AND P2 applyRef will give Invalid(NonEmptyList(errorOnP1, errorOnP2)) instead of Left(combinedError)
Damien Favre
@benderpremier
Hi, I was wondering if someone had already developed something around typeclass derivation for refined types. e.g. given I have an Ordering[Int] in scope derive automatically an Ordering[Int Refined Positive] ?
Frank Thomas
@fthomas
Frank Thomas
@fthomas
@Zhen-hao internally refined creates a Result[And[Result[P1], Result[P2]]] before this whole Result is translated to a String but there is no API that exposes the Result. A Result is either Passed or Failed and would allow in your example to inspect which of the predicates P1 and P2 failed.
Zhenhao Li
@Zhen-hao
thanks! I will give it a try when I get more time
Damien Favre
@benderpremier
Say I have positive integers on which I map _ % 3. Is there an alternative to using refineV[Interval.Closed[0,2]](x) that doesn’t wraps the result in an Either (Knowing that since I do a modulo, all possible positive integers will satisfy the predicate ? Should I do something with singleton-ops ?
Damien Favre
@benderpremier
for the moment I ended up using unsafeFrom(_ % 3) but I assume kind of an anti pattern
Piyush Purang
@ppurang
A very general question here - does any one know the limitations of refined under scala 3? Seems like val u : NonEmptyString = "u" doesn't work as intended and in this case what would be an okish work around?
[error] 85 |  val prefix: NonEmptyString = "u"
[error]    |                               ^^^
[error]    |    Found:    ("u" : String)
[error]    |    Required: eu.timepit.refined.types.all.NonEmptyString
[error]    |
[error]    |    The following import might make progress towards fixing the problem:
[error]    |
[error]    |      import eu.timepit.refined.auto.autoUnwrap
^that import is enabled
Dmytro Mitin
@DmytroMitin
And implicit conversions in eu.timepit.refined.auto are macro-based.
Dominic Egger
@GrafBlutwurst
Hey. I was wondering if it's possible to summon a runtime representation of a Predicate namely for logging puproses, I can't log the values because of sensitivity concerns but want to log the predicate it fails. But I can't find anything in the code
Dominic Egger
@GrafBlutwurst
Right now I just have my own encoding using refineDescribed[V, P](implicit validate:Validate[V,P], description: DescribeRefinement[P]): Either[RefinementError[P], V Refined P] but I want to avoid reinventing the wheel
Brian P. Holt
@bpholt

I was surprised to learn today that

val x: PosInt = 5 << 20

compiles fine during the compile sbt task, but when compile:doc runs, it blows up:

[error] /…code.scala: compile-time refinement only works with literals
[error]   private val x: PosInt = 5 << 20
[error]                             ^
[info] Int(5242880) <: eu.timepit.refined.types.all.PosInt?
[info] false
[info] No documentation generated with unsuccessful compiler run

I'm curious why it's inconsistent. What is doc doing differently that would cause this? (Scala 2.12.12, if it matters)

Brian P. Holt
@bpholt
Is it possible to use capture groups in a MatchesRegex predicate, and then extract the captured value(s) somehow?
Aleksei Shamenev
@coffius

Hi there 👋
I wonder if it is possible to validate a size of a string in compile time?

In my case I'd like to check currency codes and make sure that all code's values are strings with 3 chars in length.
I have defined the corresponding type alias as type _Code = String Refined Size[W.3.T]
But when I try to use it like this

private val test: _Code = "123"

I get this compilation error

type mismatch;
found   : String("123")
required: _Code

And it is unclear for me either it is impossible to validate this rule during compilation or I am missing some imports.

Aleksei Shamenev
@coffius
Alan Devlin
@spf3000
Hi everyone? Wondering if there is an idiomatic solution for the double definition error with refined types as parameters?
 
def getTrees(a: TreeID): List[Tree]
def getTrees(a: PlantID): List[Tree]
====>
double definition:
...
have same type after erasure: (a: String):

Oron Port
@soronpo
@spf3000 have you tried adding a dummy implicit argument?
def getTrees(a: PlantID)(implicit di : DummyImplicit): List[Tree]
Alan Devlin
@spf3000
@soronpo I didn't know about that trick - it's very neat - thanks :)
Jakub Kozłowski
@kubukoz:matrix.org
[m]
hey, are there plans to support refined macros in dotty?
Frank Thomas
@fthomas
@kubukoz:matrix.org I'm not sure yet if they can be ported to Scala 3. The Scala 2 macros use eval which is not available in Scala 3. Maybe if all Validate instances are declared as inline, it would be possible to do the validations at compile-time
Jakub Kozłowski
@kubukoz:matrix.org
[m]
I see
Frank Thomas
@fthomas
I experimented a little bit with implementing the refine macro in Scala 3 here: fthomas/refined#921 . It seems to be possible for predicates that are implemented in terms of functions like >, !, ==, etc. that can be evaluated at compile-time but it would break down for more complex predicates like MatchesRegex, Size, etc.
Oron Port
@soronpo
@fthomas did you try using compiletime.ops?
And I also think there is more to add there by PR-ing to dotty with what is required.
Both for refined and singleton-ops.
I haven't had a chance to look at this yet, but once I finish my Phd, I will get on that.
Hopefully during May