Add more ensure functions

[ustitc]

• Added ensure(condition: Boolean) for simple use-cases:

companion object : Exact<String, NotBlankString> by Exact({
   ensure(it.isNotBlank()) // use default ExactError in case of error
   NotBlankString(it)
})

• Renamed to ensureExact because it conflicted with existing ensure from core. Exact is a functional interface and ide struggles to understand what function to use, ensure(boolean, () -> Error) or ensure(boolean, Exact<Boolean, ...>):

companion object : Exact<Int, ID> by Exact({
  ensure(it > 0) { ExactError("Some error") } // arrow.exact.ensure is used instead of arrow.core.raise.ensure
  ID(it)
})

• Added more ensureExact functions for composing Exacts
• Explicitly define all combination of ensureExact instead of using defaults for better experience in ide:

[ILIYANGERMANOV]

@ustits looks good. I just don't understand what's the value of having an Exact's ensure and not simply re-using the Raise's one?

[ustitc]

@ILIYANGERMANOV the main reason is to be able to reuse Exacts. I have such an example:

@JvmInline
value class Name private constructor(private val value: String) {

    companion object : ExactEither<NameError, String, Name> by ExactEither({
        ensure(it.isNotBlank()) { BlankName }
        ensure(it.length <= 32) { LargeName }
        Name(it)
    })
}

And I have Currency class which has the same logic for validation. With help of ensureExact instead of copy-pasting I can reuse Name:

@JvmInline
value class Currency private constructor(private val name: String) {

    companion object : Exact<String, Currency> by Exact({
        ensureExact(it, Name)
        Currency(it)
    })
}

[ILIYANGERMANOV]

Makes sense - thanks for the example! I'm wondering if we can make ensureExact(it, Name) nicer? But I don't have any bright ideas atm. Good addition to the library 👏