go spec: restricted expressions may still be parenthesized
No language change.
- added a few examples with parentheses
- added a corresponding sentence to assignments
(this explicitly permits: (_) = 0, currently allowed by 6g,
gofmt, but marked as an error by gccgo).
R=rsc, r, iant
CC=golang-dev
https://golang.org/cl/4446071
diff --git a/doc/go_spec.html b/doc/go_spec.html
index 886f89d..e8f7894 100644
--- a/doc/go_spec.html
+++ b/doc/go_spec.html
@@ -1,5 +1,5 @@
<!-- title The Go Programming Language Specification -->
-<!-- subtitle Version of Apr 22, 2011 -->
+<!-- subtitle Version of May 2, 2011 -->
<!--
TODO
@@ -3522,10 +3522,9 @@
<p>
Function calls, method calls, and receive operations
-can appear in statement context.
+can appear in statement context. Such statements may be parenthesized.
</p>
-
<pre class="ebnf">
ExpressionStmt = Expression .
</pre>
@@ -3534,6 +3533,7 @@
h(x+y)
f.Close()
<-ch
+(<-ch)
</pre>
@@ -3604,15 +3604,15 @@
<p>
Each left-hand side operand must be <a href="#Address_operators">addressable</a>,
-a map index expression,
-or the <a href="#Blank_identifier">blank identifier</a>.
+a map index expression, or the <a href="#Blank_identifier">blank identifier</a>.
+Operands may be parenthesized.
</p>
<pre>
x = 1
*p = f()
a[i] = 23
-k = <-ch
+(k) = <-ch // same as: k = <-ch
</pre>
<p>
@@ -4131,7 +4131,7 @@
print("received ", i1, " from c1\n")
case c2 <- i2:
print("sent ", i2, " to c2\n")
-case i3, ok := <-c3:
+case i3, ok := (<-c3): // same as: i3, ok := <-c3
if ok {
print("received ", i3, " from c3\n")
} else {