# ^response:stream[]: the headers go with the first part, the result of @main is not sent
@main[][before;error;failed]
not sent
# the first field of the response is not a header: see the failed start below
$response:x-table[^table::create{a}]
$response:x-test[sent with the first part]
$before[$response:started]
# $response:started can not be assigned
^try{ $response:started[stream] }{ $exception.handled(true) $error[$exception.comment] }
# a part is checked before the headers are sent
^try{ ^response:stream(true) }{ $exception.handled(true) $response:x-bool[$exception.comment] }
^try{ ^response:stream[^file::stat[464.html]] }{ $exception.handled(true) $response:x-stat[$exception.comment] }
# the headers are prepared before the state is set: a failure is an ordinary error, nothing is sent
^try{ ^response:stream[never sent] }{ $exception.handled(true) $failed[$exception.comment, started: [$response:started]] }
$response:x-table[ok]
^response:stream[1. string, untainted: ^taint[<b>]
]
not sent either
^response:stream[^file::create[text;part.txt;2. file
]]
$response:x-late[too late, not sent]
^response:stream[3. number and void: |]
^response:stream(3)
^response:stream[$void]
^response:stream[|
]
^check{^response:stream[$.a[1]]}
^check{^response:stream[^table::create{a}]}
^check{^response:stream{code}}
^response:stream[5. state, before the first part: [$before], assignment: $error, failed start: $failed, now: [$response:started]
]
^response:stream[6. the last part
]

@check[code]
^try{$code}{ $exception.handled(true) ^response:stream[4. $exception.comment^#0A] }

@postprocess[body]
^response:stream[not sent: @postprocess is not called]