Namespace List
Here is a list of all documented namespaces with brief descriptions:

proton | The main Proton namespace
codec | Unsettled API - AMQP data encoding and decoding
start | Unsettled API - Start encoding a complex type
finish | Unsettled API - Finish inserting or extracting a complex type
decoder | Unsettled API - A stream-like decoder from AMQP bytes to C++ values
encoder | Unsettled API - A stream-like encoder from C++ values to AMQP bytes
io | Unsettled API - Interfaces for IO integration
mutable_buffer | Unsettled API - A pointer to a mutable memory region with a size
const_buffer | Unsettled API - A pointer to an immutable memory region with a size
connection_driver | Unsettled API - An AMQP driver for a single connection
annotation_key | A key for use with AMQP annotation maps
binary | Arbitrary binary data
byte_array | Arbitrary fixed-size data
connection | A connection to a remote AMQP peer
connection_options | Options for creating a connection
container | A top-level container of connections, sessions, and links
decimal32 | A 32-bit decimal floating-point value
decimal64 | A 64-bit decimal floating-point value
decimal128 | A 128-bit decimal floating-point value
delivery | A received message
delivery_mode | The message delivery policy to establish when opening a link
duration | A span of time in milliseconds
endpoint | The base class for session, connection, and link
error | The base Proton error
timeout_error | An operation timed out
conversion_error | An error converting between AMQP and C++ data
error_condition | Describes an endpoint error state
returned | A return type for container methods
link | A named channel for sending or receiving messages
listen_handler | Unsettled API - A handler for incoming connections
listener | A listener for incoming connections
map | A collection of key-value pairs
message | An AMQP message
message_id | An AMQP message ID
messaging_handler | A handler for Proton messaging events
receiver | A channel for receiving messages
receiver_options | Options for creating a receiver
reconnect_options | Unsettled API - Options for reconnect and failover after connection loss
sasl | SASL information
scalar | A holder for an instance of any scalar AMQP type
scalar_base | The base class for scalar types
sender | A channel for sending messages
sender_options | Options for creating a sender
session | A container of senders and receivers
session_options | Options for creating a session
source | A point of origin for messages
source_options | Options for creating a source node for a sender or receiver
ssl | SSL information
ssl_certificate | Unsettled API - An SSL certificate
ssl_server_options | Unsettled API - SSL configuration for inbound connections
ssl_client_options | Unsettled API - SSL configuration for outbound connections
symbol | A string that represents the AMQP symbol type
target | A destination for messages
target_options | Options for creating a target node for a sender or receiver
terminus | One end of a link, either a source or a target
timestamp | A 64-bit timestamp in milliseconds since the Unix epoch
tracker | A tracker for a sent message
transfer | The base class for delivery and tracker
transport | A network channel supporting an AMQP connection
url_error | Deprecated - Use a third-party URL library
url | Deprecated - Use a third-party URL library
uuid | A 16-byte universally unique identifier
value | A holder for any AMQP value, simple or complex
work_queue | Unsettled API - A context for thread-safe execution of work