apidiff: changes to README
Changes in response to final comments on https://go-review.googlesource.com/c/exp/+/143597.
Change-Id: I29ce24d71c0758aee4e9b4a01f990fb6eed40ffa
Reviewed-on: https://go-review.googlesource.com/c/149037
Reviewed-by: Robert Griesemer <gri@golang.org>
diff --git a/apidiff/README.md b/apidiff/README.md
index a986948..d036ee0 100644
--- a/apidiff/README.md
+++ b/apidiff/README.md
@@ -198,10 +198,10 @@
type u2 int
var V u2
```
-Here, even though `u1` and `u2` are unexported, they are still _exposed_ by the
-API: their exported fields and methods are visible to clients, so they are part
-of the API. But since the name `u1` is not visible to clients, it can
-be changed compatibly.
+Here, even though `u1` and `u2` are unexported, their exported fields and
+methods are visible to clients, so they are part of the API. But since the name
+`u1` is not visible to clients, it can be changed compatibly. We say that `u1`
+and `u2` are _exposed_: a type is exposed if a client package can declare variables of that type.
We will say that an old defined type _corresponds_ to a new one if they have the
same name, or one can be renamed to the other without otherwise changing the
@@ -225,11 +225,11 @@
### Package Compatibility
> A new package is compatible with an old one if:
-1. Each exported name in the old package's scope also appears in the new
-package's scope, and the object (constant, variable, function or type) denoted
-by that name in the old package is compatible with the object denoted by the
-name in the new package, and
-2. For every exposed type that implements an exposed interface in the old package,
+>1. Each exported name in the old package's scope also appears in the new
+>package's scope, and the object (constant, variable, function or type) denoted
+>by that name in the old package is compatible with the object denoted by the
+>name in the new package, and
+>2. For every exposed type that implements an exposed interface in the old package,
> its corresponding type should implement the corresponding interface in the new package.
>
>Otherwise the packages are incompatible.
@@ -279,7 +279,7 @@
var a [C]int = [1]int{} // fails with new because [2]int and [1]int are different types
```
Changes to constant values are rare, and determining whether they are compatible
-are not is better left to the user, so the tool reports them.
+or not is better left to the user, so the tool reports them.
#### Variables
