Pull in go-flags, modified to build on Solaris

github.com/jessevdk/go-flags/group.go

@@ -0,0 +1,80 @@
+// Copyright 2012 Jesse van den Kieboom. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package flags
+
+import (
+	"errors"
+	"strings"
+)
+
+// ErrNotPointerToStruct indicates that a provided data container is not
+// a pointer to a struct. Only pointers to structs are valid data containers
+// for options.
+var ErrNotPointerToStruct = errors.New("provided data is not a pointer to struct")
+
+// Group represents an option group. Option groups can be used to logically
+// group options together under a description. Groups are only used to provide
+// more structure to options both for the user (as displayed in the help message)
+// and for you, since groups can be nested.
+type Group struct {
+	// A short description of the group. The
+	// short description is primarily used in the builtin generated help
+	// message
+	ShortDescription string
+
+	// A long description of the group. The long
+	// description is primarily used to present information on commands
+	// (Command embeds Group) in the builtin generated help and man pages.
+	LongDescription string
+
+	// All the options in the group
+	options []*Option
+
+	// All the subgroups
+	groups []*Group
+
+	data interface{}
+}
+
+// AddGroup adds a new group to the command with the given name and data. The
+// data needs to be a pointer to a struct from which the fields indicate which
+// options are in the group.
+func (g *Group) AddGroup(shortDescription string, longDescription string, data interface{}) (*Group, error) {
+	group := newGroup(shortDescription, longDescription, data)
+
+	if err := group.scan(); err != nil {
+		return nil, err
+	}
+
+	g.groups = append(g.groups, group)
+	return group, nil
+}
+
+// Groups returns the list of groups embedded in this group.
+func (g *Group) Groups() []*Group {
+	return g.groups
+}
+
+// Options returns the list of options in this group.
+func (g *Group) Options() []*Option {
+	return g.options
+}
+
+// Find locates the subgroup with the given short description and returns it.
+// If no such group can be found Find will return nil. Note that the description
+// is matched case insensitively.
+func (g *Group) Find(shortDescription string) *Group {
+	lshortDescription := strings.ToLower(shortDescription)
+
+	var ret *Group
+
+	g.eachGroup(func(gg *Group) {
+		if gg != g && strings.ToLower(gg.ShortDescription) == lshortDescription {
+			ret = gg
+		}
+	})
+
+	return ret
+}