notes

notes/0.13.13.markdown

@@ -1,8 +1,7 @@
 
 ### Fixes with compatibility implications
 
-- Deprecates the old symbolic operators, to be removed in sbt 1.0. See below for more details.
-- Deprecates the old sbt 0.10 syntax, to be removed in sbt 1.0. See http://www.scala-sbt.org/0.13/docs/Migrating-from-sbt-012x.html for more details. [#2763][2763]/[#2764][2764] by [@dwijnand][@dwijnand]
+- Deprecates the old sbt 0.12 DSL, to be removed in sbt 1.0. See below for more details.
 - The `.value` method is deprecated for input tasks. Calling `.value` on an input key returns an `InputTask[A]`,
   which is completely unintuitive and often results in a bug. In most cases `.evaluated` should be called,
   which returns `A` by evaluating the task.
@@ -90,21 +89,41 @@ by overriding `derivedProjects`:
 
 [#2532][2532]/[#2717][2717]/[#2738][2738] by [@eed3si9n][@eed3si9n]
 
-### Deprecate old operators
+### Deprecate old sbt 0.12 DSL
 
-The no-longer-documented operators `<<=`, `<+=`, and `<++=` are deprecated,
+The no-longer-documented operators `<<=`, `<+=`, and `<++=` and tuple enrichments are deprecated,
 and will be removed in sbt 1.0.
 
-For `<<=`, the suggested migration would be to use either `:=` or `~=` operators.
-The RHS of `<<=` takes an `Initialize[_]` expression, which can be converted to `:=` style
-by wrapping the expression in parenthesis, and calling `.value` at the end.
-For example:
+Generally,
 
-    key := (key.dependsOn(compile in Test)).value
+    task3 <<= (task1, task2) map { (t1, t2) => println(t1 + t2); t1 + t2 }
 
-For `<+=` and `<++=`, use `+= { x.value }` and `++= { x.value }`.
+should migrate to
 
-[#2716][2716] by [@eed3si9n][@eed3si9n]
+    task3 := {
+      println(task1.value + task2.value)
+      task1.value + task2.value
+    }
+
+Except for source generators, which requires task values:
+
+    sourceGenerators in Compile <+= buildInfo
+
+This becomes:
+
+    sourceGenerators in Compile += buildInfo.taskValue
+
+Another exception is input task:
+
+    run <<= docsRunSetting
+
+This becomes:
+
+    run := docsRunSetting.evaluated
+
+See [Migrating from sbt 0.12.x](http://www.scala-sbt.org/0.13/docs/Migrating-from-sbt-012x.html) for more details.
+
+[#2716][2716]/[#2763][2763]/[#2764][2764] by [@eed3si9n][@eed3si9n] and [@dwijnand][@dwijnand]
 
   [g8]: http://www.foundweekends.org/giter8/
   [eed3si9n/hello.g8]: https://github.com/eed3si9n/hello.g8