From: Rob Pike <r@golang.org>
Date: Fri, 8 May 2009 23:24:55 +0000 (-0700)
Subject: Package unsafe is undocumented.  By installing (but not compiling) this file,
X-Git-Tag: weekly.2009-11-06~1670
X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=20850fc014c27a9df4f4201844c0136725202800;p=gostls13.git

Package unsafe is undocumented.  By installing (but not compiling) this file,
which contains only declarations, we can have godoc present documentation
for the package.

R=gri,rsc
DELTA=44  (43 added, 0 deleted, 1 changed)
OCL=28555
CL=28588
---

diff --git a/src/lib/unsafe/unsafe.go b/src/lib/unsafe/unsafe.go
new file mode 100644
index 0000000000..b19af405b6
--- /dev/null
+++ b/src/lib/unsafe/unsafe.go
@@ -0,0 +1,44 @@
+// 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.
+
+/*
+	The unsafe package contains operations that step around the type safety of Go programs.
+ */
+package unsafe
+
+// ArbitraryType is here for the purposes of documentation only and is not actually
+// part of the unsafe package.  It represents the type of an arbitrary Go expression.
+type ArbitraryType int
+
+// Pointer represents a pointer to an arbitrary type.  There are three special operations
+// available for type Pointer that are not available for other types.
+//	1) A pointer value of any type can be converted to a Pointer.
+//	2) A uintptr can be converted to a Pointer.
+//	3) A Pointer can be converted to a uintptr.
+// Pointer therefore allows a program to defeat the type system and read and write
+// arbitrary memory. It should be used with extreme care.
+type	Pointer	*ArbitraryType
+
+// Sizeof returns the size in bytes occupied by the value v.  The size is that of the
+// "top level" of the value only.  For instance, if v is a slice, it returns the size of
+// the slice descriptor, not the size of the memory referenced by the slice.
+func	Sizeof(v ArbitraryType) int
+
+// Offsetof returns the offset within the struct of the field represented by v,
+// which must be of the form struct_value.field.  In other words, it returns the
+// number of bytes between the start of the struct and the start of the field.
+func	Offsetof(v ArbitraryType) int
+
+// Alignof returns the alignment of the value v.  It is the minimum value m such
+// that the address of a variable with the type of v will always always be zero mod m.
+// If v is of the form obj.f, it returns the alignment of field f within struct object obj.
+func	Alignof(v ArbitraryType) int
+
+// Reflect unpacks an interface value into its internal value word and its type string.
+// The boolean indir is true if the value is a pointer to the real value.
+func	Reflect(i interface {}) (value uint64, typestring string, indir bool)
+
+// Unreflect inverts Reflect: Given a value word, a type string, and the indirect bit,
+// it returns an empty interface value with those contents.
+func	Unreflect(value uint64, typestring string, indir bool) (ret interface {})