Basic.Contenttype t = {content_type : Amqp_client_lib.Types.shortstr option;content_encoding : Amqp_client_lib.Types.shortstr option;headers : Amqp_client_lib.Types.table option;delivery_mode : Amqp_client_lib.Types.octet option;priority : Amqp_client_lib.Types.octet option;correlation_id : Amqp_client_lib.Types.shortstr option;reply_to : Amqp_client_lib.Types.shortstr option;expiration : Amqp_client_lib.Types.shortstr option;message_id : Amqp_client_lib.Types.shortstr option;timestamp : Amqp_client_lib.Types.timestamp option;amqp_type : Amqp_client_lib.Types.shortstr option;user_id : Amqp_client_lib.Types.shortstr option;app_id : Amqp_client_lib.Types.shortstr option;reserved : Amqp_client_lib.Types.shortstr option;}val init :
?content_type:Amqp_client_lib.Types.shortstr ->
?content_encoding:Amqp_client_lib.Types.shortstr ->
?headers:Amqp_client_lib.Types.table ->
?delivery_mode:Amqp_client_lib.Types.octet ->
?priority:Amqp_client_lib.Types.octet ->
?correlation_id:Amqp_client_lib.Types.shortstr ->
?reply_to:Amqp_client_lib.Types.shortstr ->
?expiration:Amqp_client_lib.Types.shortstr ->
?message_id:Amqp_client_lib.Types.shortstr ->
?timestamp:Amqp_client_lib.Types.timestamp ->
?amqp_type:Amqp_client_lib.Types.shortstr ->
?user_id:Amqp_client_lib.Types.shortstr ->
?app_id:Amqp_client_lib.Types.shortstr ->
?reserved:Amqp_client_lib.Types.shortstr ->
unit ->
t