Implement support for unqiue config instances.

This commit adds a new type, SpewState, which can be used to create
instances with unique configuration options.  The methods of SpewState are
equivalent to the top-level functions.  Full documentation and examples
are included.

1 files changed, 13 insertions, 4 deletions

diff --git a/spew/doc.go b/spew/doc.go
index 61c0091..94db62d 100644
--- a/spew/doc.go
+++ b/spew/doc.go
@@ -58,20 +58,29 @@ printing style, use the convenience wrappers Printf, Fprintf, etc with either
 
 Configuration Options
 
+Configuration of spew is handled by fields in the ConfigState type.  For
+convenience, all of the top-level functions use a global state available
+via the spew.Config global.
+
+It is also possible to create a SpewState instance which provides a unique
+ConfigState accessible via the Config method.  The methods of SpewState are
+equivalent to the top-level functions.  This allows concurrent configuration
+options.  See the SpewState documentation for more details.
+
 The following configuration options are available:
-	spew.Config.MaxDepth
+	* MaxDepth
 		Maximum number of levels to descend into nested data structures.
 		There is no limit by default.
 
-	spew.Config.Indent
+	* Indent
 		String to use for each indentation level for Dump functions.
 		It is a single space by default.  A popular alternative is "\t".
 
-	spew.Config.DisableMethods
+	* DisableMethods
 		Disables invocation of error and Stringer interface methods.
 		Method invocation is enabled by default.
 
-	spew.Config.DisablePointerMethods
+	* DisablePointerMethods
 		Disables invocation of error and Stringer interface methods on types
 		which only accept pointer receivers from non-pointer variables.
 		Pointer method invocation is enabled by default.