Created
October 23, 2014 20:42
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The good, bad, and ugly of implicits with +
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| package com.joescii | |
| import org.scalatest.{ShouldMatchers, FlatSpecLike} | |
| /** | |
| * Created by jbarnes on 10/23/2014. | |
| */ | |
| class ImplicitSpecs extends FlatSpecLike with ShouldMatchers { | |
| "Scala implicits" should "act like their java counterparts" in { | |
| val java = new MyJavaClass | |
| java.a should equal (1 + "1") | |
| java.b should equal (1 + 1 + "1") | |
| java.c should equal ("1" + 1 + 1) | |
| java.d should equal (1 + "1" + 1) | |
| } | |
| } |
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| package com.joescii; | |
| /** | |
| * Created by jbarnes on 1/24/14. | |
| */ | |
| public class MyJavaClass { | |
| public String a = 1 + "1"; | |
| public String b = 1 + 1 + "1"; | |
| public String c = "1" + 1 + 1; | |
| public String d = 1 + "1" + 1; | |
| } |
Thanks for taking the time to do this - appreciate it!
The problem is exactly that Scala values (consistency with Java) more than (strict strong-typing) :)
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After a second look at your original tweet, I realize my reply was dumb. I didn't see all of the examples thanks to the hootsuite twitter client on my iPhone. 👎
So only
"1" + 1 + 1is java-interop (which is the only one I saw originally). This is because Scala wholly reuses java.lang.String, which has a+defined accepting anyjava.lang.Object, and henceAnyfrom Scala.As for the others.... yes, they are implicit conversions (facepalm). I agree on the principle that you dislike it, but I also get that the
+is not consistent across the four examples. Scala's approach is also consistent with Java, which is an awfully heavy influence on the language.Ok, so I did a dumb, but hopefully this explanation is still helpful for you. :)