spec: add an example of a trivially invalid interface
In preparation for the forthcoming spec changes for #6977.
While at it, modernize existing File example that dates
back all the way to commit 18c5b488a3b.
Change-Id: Id10e4df0513e3de15bd58867222923eefa9473ea
Reviewed-on: https://go-review.googlesource.com/c/go/+/187978
Reviewed-by: Rob Pike <r@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
diff --git a/doc/go_spec.html b/doc/go_spec.html
index fb4341b..89732fb 100644
--- a/doc/go_spec.html
+++ b/doc/go_spec.html
@@ -1,6 +1,6 @@
<!--{
"Title": "The Go Programming Language Specification",
- "Subtitle": "Version of May 14, 2019",
+ "Subtitle": "Version of July 31, 2019",
"Path": "/ref/spec"
}-->
@@ -1257,11 +1257,19 @@
</p>
<pre>
-// A simple File interface
+// A simple File interface.
interface {
- Read(b Buffer) bool
- Write(b Buffer) bool
- Close()
+ Read([]byte) (int, error)
+ Write([]byte) (int, error)
+ Close() error
+}
+</pre>
+
+<pre>
+interface {
+ String() string
+ String() string // illegal: String not unique
+ _(x int) // illegal: method must have non-blank name
}
</pre>
@@ -1272,9 +1280,9 @@
</p>
<pre>
-func (p T) Read(b Buffer) bool { return … }
-func (p T) Write(b Buffer) bool { return … }
-func (p T) Close() { … }
+func (p T) Read(p []byte) (n int, err error) { return … }
+func (p T) Write(p []byte) (n int, err error) { return … }
+func (p T) Close() error { return … }
</pre>
<p>
