implement new restrictions on what
can be compared/hashed.
R=r
DELTA=351 (201 added, 80 deleted, 70 changed)
OCL=23423
CL=23481
diff --git a/test/cmp1.go b/test/cmp1.go
new file mode 100644
index 0000000..82e932f
--- /dev/null
+++ b/test/cmp1.go
@@ -0,0 +1,66 @@
+// $G $D/$F.go && $L $F.$A && ./$A.out
+
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "unsafe"
+
+func use(bool) { }
+
+func stringptr(s string) uintptr {
+ return *(&s).(unsafe.Pointer).(*uintptr);
+}
+
+func isfalse(b bool) {
+ if b { panicln("wanted false, got true") } // stack will explain where
+}
+
+func istrue(b bool) {
+ if !b { panicln("wanted true, got false") } // stack will explain where
+}
+
+func main()
+{
+ var a []int;
+ var b map[string]int;
+
+ var c string = "hello";
+ var d string = "hel"; // try to get different pointer
+ d = d + "lo";
+ if stringptr(c) == stringptr(d) {
+ panic("compiler too smart -- got same string")
+ }
+
+ var e = make(chan int);
+
+ var ia interface{} = a;
+ var ib interface{} = b;
+ var ic interface{} = c;
+ var id interface{} = d;
+ var ie interface{} = e;
+
+ // these comparisons are okay because
+ // string compare is okay and the others
+ // are comparisons where the types differ.
+ isfalse(ia == ib);
+ isfalse(ia == ic);
+ isfalse(ia == id);
+ isfalse(ib == ic);
+ isfalse(ib == id);
+ istrue(ic == id);
+ istrue(ie == ie);
+
+ // map of interface should use == on interface values,
+ // not memory.
+ // TODO: should m[c], m[d] be valid here?
+ var m = make(map[interface{}] int);
+ m[ic] = 1;
+ m[id] = 2;
+ if m[ic] != 2 {
+ panic("m[ic] = ", m[ic]);
+ }
+}
+
