From 1f2834e458c4c28fe3264968a80f451636c232e4 Mon Sep 17 00:00:00 2001
From: Boris Kolpackov <boris@codesynthesis.com>
Date: Wed, 22 Feb 2012 12:28:06 +0200
Subject: Add support for composite object ids

New pragma id_type (member). New test: common/composite-id. The composite
example has also been updated.
---
 composite/README     | 17 +++++++-------
 composite/driver.cxx | 11 ++++++---
 composite/person.hxx | 63 ++++++++++++++++++++++++++++++++++++++++++++++++----
 3 files changed, 76 insertions(+), 15 deletions(-)

diff --git a/composite/README b/composite/README
index e33e7a9..2368784 100644
--- a/composite/README
+++ b/composite/README
@@ -1,16 +1,17 @@
 This example shows how to use composite value types as data members in objects
-and other value types, as element types in containers, and as base types for
-other composite value types. It also shows how to use composite value type
-data members in queries.
+(including as object id members) and other value types, as element types in
+containers, and as base types for other composite value types. It also shows
+how to use composite value type data members in queries.
 
 The example consists of the following files:
 
 person.hxx
-  Header file defining the 'basic_name', 'name_extras', and 'name' composite
-  value types. It also defines the 'phone_numbers' composite value type as
-  an instantiation of the 'std::pair' class template. Finally it defines
-  the 'person' persistent class which uses the 'name' and 'phone_numbers'
-  value types in its data members.
+  Header file defining the 'basic_name', 'name_extras', 'name', and
+  'email_address' composite value types. It also defines the 'phone_numbers'
+  composite value type as an instantiation of the 'std::pair' class template
+  Finally it defines the 'person' persistent class which uses 'email_address'
+  as its object id as well as 'name' and 'phone_numbers' in its other data
+  members.
 
 person-odb.hxx
 person-odb.ixx
diff --git a/composite/driver.cxx b/composite/driver.cxx
index cb77acd..aaedf17 100644
--- a/composite/driver.cxx
+++ b/composite/driver.cxx
@@ -24,9 +24,13 @@ main (int argc, char* argv[])
 
     // Create a person object.
     //
-    unsigned int id;
+    email_address id;
     {
-      person p ("Joe", "Dirt", "Mr", phone_numbers ("555 5555", "666 6666"));
+      person p ("joe@example.com",
+                "Joe",
+                "Dirt",
+                "Mr",
+                phone_numbers ("555 5555", "666 6666"));
 
       transaction t (db->begin ());
       id = db->persist (p);
@@ -57,7 +61,8 @@ main (int argc, char* argv[])
 
       name& n (joe->name ());
 
-      cout << n.title () << " " << n.first () << " " << n.last () << endl;
+      cout << n.title () << " " << n.first () << " " << n.last () << " "
+           << '<' << joe->email ().address () << '>' << endl;
 
       name_extras& ne (n.extras ());
 
diff --git a/composite/person.hxx b/composite/person.hxx
index 4496180..c80e2d8 100644
--- a/composite/person.hxx
+++ b/composite/person.hxx
@@ -129,16 +129,71 @@ private:
 typedef std::pair<std::string, std::string> phone_numbers;
 #pragma db value(phone_numbers)
 
+// We can also use a composite value type as an object id.
+//
+#pragma db value
+class email_address
+{
+public:
+  email_address () {}
+  email_address (const std::string& address)
+  {
+    std::string::size_type p (address.find ('@'));
+    recipient_.assign (address, 0, p);
+    domain_.assign (address, p + 1, std::string::npos);
+  }
+
+  const std::string&
+  recipient () const
+  {
+    return recipient_;
+  }
+
+  const std::string&
+  domain () const
+  {
+    return domain_;
+  }
+
+  std::string
+  address () const
+  {
+    return recipient_ + '@' + domain_;
+  }
+
+private:
+  friend class odb::access;
+
+  std::string recipient_;
+  std::string domain_;
+};
+
+inline bool
+operator< (const email_address& x, const email_address& y)
+{
+  return x.recipient () < y.recipient () ||
+    (x.recipient () == y.recipient () && x.domain() < y.domain ());
+}
+
 #pragma db object
 class person
 {
 public:
-  person (const std::string& first,
+  person (const std::string& email,
+          const std::string& first,
           const std::string& last,
           const std::string& title,
           const phone_numbers& phone)
-      : name_ (first, last, title), phone_ (phone)
+      : email_ (email), name_ (first, last, title), phone_ (phone)
+  {
+  }
+
+  // Email address.
+  //
+  const email_address&
+  email () const
   {
+    return email_;
   }
 
   // Name.
@@ -170,8 +225,8 @@ private:
 
   person (): name_ ("", "", "") {}
 
-  #pragma db id auto
-  unsigned long id_;
+  #pragma db id
+  email_address email_;
 
   name_type name_;
   phone_numbers phone_;
-- 
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