How to import TripleEquals (===) only?

[Andreas Joseph Krogh]

Hi.

I'd like to import as specific as possible the === operator, how do I do that?

Thanks.

--
Andreas

[Brian McKenna]

import scalaz.syntax.equal._

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[Parakhonskiy Gleb]

Hi, Brian's answer will surely do the thing

For the sake of completeness, threre's another way: 

import scalaz.Scalaz.ToEqualOps

[Andreas Joseph Krogh]

Hm, sorry but none of these worked.

import scalaz.Scalaz.ToEqualOps

val f = "nissefisk"
val i = 123
val t = f === i

Error:(29, 13) value === is not a member of String
        val t = f === i
                  ^

If I replace with:

import scalaz.Scalaz._

I get correct error:
Error:(29, 17) type mismatch;
 found   : Int
 required: String
		val t = f === i
		              ^

What am I missing?

Thanks.

[Robert Norris]

You need the syntax for the typeclass as well as the instances for types you'd like to compare.

scala> import scalaz.syntax.equal._ // syntax for the typeclass

import scalaz.syntax.equal._

scala> import scalaz.std.string._ // instances for String

import scalaz.std.string._

scala> "abc" === "abc"

res0: Boolean = true

scala> "abc" =/= "def"

res1: Boolean = true

scala> "abc" === 1

<console>:14: error: type mismatch;

 found   : Int(1)

 required: String

              "abc" === 1

                        ^

[Andreas Joseph Krogh]

Thanks!