ReadableByteStreamController.error(reason) performs controller cleanup before the stream’s pending BYOB read is observed as rejected. It clears pending pull-into descriptors, resets the byte queue, clears source algorithms and then errors the stream. The read-into request rejects because the stream enters the errored state; it is not fulfilled with a short view and its partially filled bytes do not become a later queue result.
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Start with a Uint16Array BYOB read that has received two of four requested bytes. Call controller.error(‘device-fault’) and keep separate ledgers for the descriptor, controller queue, stream stored error, read promise and reader.closed. Then change the timing: error before any bytes, after a committed view, after close, and while a default reader is active. The cases show which work is discarded and which already-settled result remains historical.
ROUTE 1 · CHAPTERS 1–3
Build the first model
Name the input, state, conversion or predicate before following user-visible results.
ROUTE 2 · CHAPTERS 4–5
Trace the decisive branch
Work the accepted path and the nearest boundary case with original examples.
ROUTE 3 · CHAPTERS 6–8
Change one premise
Rebuild the mechanism when state, value, realm, timing or object kind changes.
ROUTE 4 · CHAPTERS 9–10
Handle limits and failures
Keep abrupt completion, availability and application limits visible.
ROUTE 5 · CHAPTERS 11–12
Verify and explain
Use a decisive fixture, changed-context check and concise final account.
Chapter contents
Build the first model · Chapters 1–3
1. Name cleanup and rejection separately
Change one premise · Chapters 6–8
Handle limits and failures · Chapters 9–10
Verify and explain · Chapters 11–12
The short answer is that the controller clears its byte-specific pending state before the stream error operation rejects outstanding reads. Chapter 1 focuses on name cleanup and rejection separately. Begin with keep controller state, pending pull-into descriptors, bytes filled, queue entries, queueTotalSize, current BYOB request, stored error, read-into requests and reader.closed settlement in separate columns. Writing those facts first prevents a familiar label or final summary value from replacing the mechanism or measurement basis that actually decides the result.
Worked example. request two Uint16 elements, supply one complete element and then report device-fault. Treat every stated value as part of a controlled teaching fixture. Record the starting state before the operation, then record each conversion, selection, calculation, check or state transition in order. If a prerequisite fails, stop the trace there rather than inferring later effects from the usual path.
A useful first-principles question for name cleanup and rejection separately is: what must already be true before this step can run? Use the rule above to separate the input contract from the result. Follow object identity, state and returned value independently. Two branches can print similar data while differing in ownership, timing, brand or future capability.
Now change exactly one premise. report the same fault before any bytes arrive and compare the empty and partially filled ledgers. Recalculate the trace from the changed fact rather than editing the old conclusion. Name the earliest event that differs, carry that difference through the remaining steps, and say which observations stay the same because their prerequisites did not change.
The main limit is this: a rejected read does not expose the discarded partial buffer as a successful result. Keep language semantics separate from processor strategy, host scheduling, browser support, trust policy and the meaning assigned by an application. A focused example can establish the stated mechanism without pretending to settle those broader questions.
Practical evidence check. log cleanup fields before recording promise rejection. Capture the reported values and failure conditions, but also preserve the calculation or event trail that led to them. A check that asserts only the last number or label can pass even when an earlier selection, conversion, grouping, state change or measurement basis was wrong.
A concise final explanation of name cleanup and rejection separately should state the starting state, the governing rule, the ordered outcome and one boundary. It should not depend on a screenshot, one software message or an unstated assumption. That form is short enough for revision and precise enough for a reproducible technical note.
The short answer is that a BYOB read transfers the supplied buffer and registers a read-into request paired with a pull-into descriptor. Chapter 2 focuses on create a pending byob fixture. Begin with keep controller state, pending pull-into descriptors, bytes filled, queue entries, queueTotalSize, current BYOB request, stored error, read-into requests and reader.closed settlement in separate columns. Writing those facts first prevents a familiar label or final summary value from replacing the mechanism or measurement basis that actually decides the result.
Worked example. read into Uint16Array length two and hold the source response after two bytes. Treat every stated value as part of a controlled teaching fixture. Record the starting state before the operation, then record each conversion, selection, calculation, check or state transition in order. If a prerequisite fails, stop the trace there rather than inferring later effects from the usual path.
A useful first-principles question for create a pending byob fixture is: what must already be true before this step can run? Use the rule above to separate the input contract from the result. Follow object identity, state and returned value independently. Two branches can print similar data while differing in ownership, timing, brand or future capability.
Now change exactly one premise. use a default reader instead and identify the read request without a consumer-supplied view. Recalculate the trace from the changed fact rather than editing the old conclusion. Name the earliest event that differs, carry that difference through the remaining steps, and say which observations stay the same because their prerequisites did not change.
The main limit is this: the caller’s original view is already transferred before the later error occurs. Keep language semantics separate from processor strategy, host scheduling, browser support, trust policy and the meaning assigned by an application. A focused example can establish the stated mechanism without pretending to settle those broader questions.
Practical evidence check. assert reader type, descriptor reader type, buffer state and read promise identity. Capture the reported values and failure conditions, but also preserve the calculation or event trail that led to them. A check that asserts only the last number or label can pass even when an earlier selection, conversion, grouping, state change or measurement basis was wrong.
A concise final explanation of create a pending byob fixture should state the starting state, the governing rule, the ordered outcome and one boundary. It should not depend on a screenshot, one software message or an unstated assumption. That form is short enough for revision and precise enough for a reproducible technical note.
The short answer is that bytes can be present in the head descriptor while the read remains pending because its minimum fill has not been met. Chapter 3 focuses on record a partial fill. Begin with keep controller state, pending pull-into descriptors, bytes filled, queue entries, queueTotalSize, current BYOB request, stored error, read-into requests and reader.closed settlement in separate columns. Writing those facts first prevents a familiar label or final summary value from replacing the mechanism or measurement basis that actually decides the result.
Worked example. write two aligned bytes toward a four-byte minimum and pause. Treat every stated value as part of a controlled teaching fixture. Record the starting state before the operation, then record each conversion, selection, calculation, check or state transition in order. If a prerequisite fails, stop the trace there rather than inferring later effects from the usual path.
A useful first-principles question for record a partial fill is: what must already be true before this step can run? Use the rule above to separate the input contract from the result. Follow object identity, state and returned value independently. Two branches can print similar data while differing in ownership, timing, brand or future capability.
Now change exactly one premise. lower the minimum in a new fixture so the same two bytes commit before the error. Recalculate the trace from the changed fact rather than editing the old conclusion. Name the earliest event that differs, carry that difference through the remaining steps, and say which observations stay the same because their prerequisites did not change.
The main limit is this: partial fill is controller work, not a consumer-visible chunk. Keep language semantics separate from processor strategy, host scheduling, browser support, trust policy and the meaning assigned by an application. A focused example can establish the stated mechanism without pretending to settle those broader questions.
Practical evidence check. capture bytes filled, minimum fill, element size and unresolved promise. Capture the reported values and failure conditions, but also preserve the calculation or event trail that led to them. A check that asserts only the last number or label can pass even when an earlier selection, conversion, grouping, state change or measurement basis was wrong.
A concise final explanation of record a partial fill should state the starting state, the governing rule, the ordered outcome and one boundary. It should not depend on a screenshot, one software message or an unstated assumption. That form is short enough for revision and precise enough for a reproducible technical note.
The short answer is that the byte-controller error operation removes every pending pull-into descriptor before resetting the queue and erroring the stream. Chapter 4 focuses on clear pending pull-intos first. Begin with keep controller state, pending pull-into descriptors, bytes filled, queue entries, queueTotalSize, current BYOB request, stored error, read-into requests and reader.closed settlement in separate columns. Writing those facts first prevents a familiar label or final summary value from replacing the mechanism or measurement basis that actually decides the result.
Worked example. call error with descriptor A partly filled and descriptor B waiting behind it. Treat every stated value as part of a controlled teaching fixture. Record the starting state before the operation, then record each conversion, selection, calculation, check or state transition in order. If a prerequisite fails, stop the trace there rather than inferring later effects from the usual path.
A useful first-principles question for clear pending pull-intos first is: what must already be true before this step can run? Use the rule above to separate the input contract from the result. Follow object identity, state and returned value independently. Two branches can print similar data while differing in ownership, timing, brand or future capability.
Now change exactly one premise. commit A before reporting the error so only B remains pending. Recalculate the trace from the changed fact rather than editing the old conclusion. Name the earliest event that differs, carry that difference through the remaining steps, and say which observations stay the same because their prerequisites did not change.
The main limit is this: clearing a list is not the same as fulfilling or closing its requests. Keep language semantics separate from processor strategy, host scheduling, browser support, trust policy and the meaning assigned by an application. A focused example can establish the stated mechanism without pretending to settle those broader questions.
Practical evidence check. assert descriptor-list length at each ordered step. Capture the reported values and failure conditions, but also preserve the calculation or event trail that led to them. A check that asserts only the last number or label can pass even when an earlier selection, conversion, grouping, state change or measurement basis was wrong.
A concise final explanation of clear pending pull-intos first should state the starting state, the governing rule, the ordered outcome and one boundary. It should not depend on a screenshot, one software message or an unstated assumption. That form is short enough for revision and precise enough for a reproducible technical note.
The short answer is that controller error resets ordinary byte queue entries and queueTotalSize so unread bytes cannot appear after the failure. Chapter 5 focuses on reset queued bytes. Begin with keep controller state, pending pull-into descriptors, bytes filled, queue entries, queueTotalSize, current BYOB request, stored error, read-into requests and reader.closed settlement in separate columns. Writing those facts first prevents a familiar label or final summary value from replacing the mechanism or measurement basis that actually decides the result.
Worked example. place bytes 9 and 10 in the queue as well as partial descriptor bytes, then error. Treat every stated value as part of a controlled teaching fixture. Record the starting state before the operation, then record each conversion, selection, calculation, check or state transition in order. If a prerequisite fails, stop the trace there rather than inferring later effects from the usual path.
A useful first-principles question for reset queued bytes is: what must already be true before this step can run? Use the rule above to separate the input contract from the result. Follow object identity, state and returned value independently. Two branches can print similar data while differing in ownership, timing, brand or future capability.
Now change exactly one premise. let a read consume the queue first and error only after that promise settles. Recalculate the trace from the changed fact rather than editing the old conclusion. Name the earliest event that differs, carry that difference through the remaining steps, and say which observations stay the same because their prerequisites did not change.
The main limit is this: queue reset does not retract a chunk already delivered to application code. Keep language semantics separate from processor strategy, host scheduling, browser support, trust policy and the meaning assigned by an application. A focused example can establish the stated mechanism without pretending to settle those broader questions.
Practical evidence check. reconcile every queued byte as delivered earlier or discarded at error. Capture the reported values and failure conditions, but also preserve the calculation or event trail that led to them. A check that asserts only the last number or label can pass even when an earlier selection, conversion, grouping, state change or measurement basis was wrong.
A concise final explanation of reset queued bytes should state the starting state, the governing rule, the ordered outcome and one boundary. It should not depend on a screenshot, one software message or an unstated assumption. That form is short enough for revision and precise enough for a reproducible technical note.
The short answer is that error removes controller algorithms so later pull or cancel scheduling cannot revive the failed source path. Chapter 6 focuses on clear source algorithms. Begin with keep controller state, pending pull-into descriptors, bytes filled, queue entries, queueTotalSize, current BYOB request, stored error, read-into requests and reader.closed settlement in separate columns. Writing those facts first prevents a familiar label or final summary value from replacing the mechanism or measurement basis that actually decides the result.
Worked example. count pull callbacks before and after error while a read remains outstanding. Treat every stated value as part of a controlled teaching fixture. Record the starting state before the operation, then record each conversion, selection, calculation, check or state transition in order. If a prerequisite fails, stop the trace there rather than inferring later effects from the usual path.
A useful first-principles question for clear source algorithms is: what must already be true before this step can run? Use the rule above to separate the input contract from the result. Follow object identity, state and returned value independently. Two branches can print similar data while differing in ownership, timing, brand or future capability.
Now change exactly one premise. create a fresh stream with the same underlying source object and show that only the new controller can pull. Recalculate the trace from the changed fact rather than editing the old conclusion. Name the earliest event that differs, carry that difference through the remaining steps, and say which observations stay the same because their prerequisites did not change.
The main limit is this: cleared algorithms belong to that controller and do not mutate unrelated source objects. Keep language semantics separate from processor strategy, host scheduling, browser support, trust policy and the meaning assigned by an application. A focused example can establish the stated mechanism without pretending to settle those broader questions.
Practical evidence check. assert pull count, controller identity and absence of later callbacks. Capture the reported values and failure conditions, but also preserve the calculation or event trail that led to them. A check that asserts only the last number or label can pass even when an earlier selection, conversion, grouping, state change or measurement basis was wrong.
A concise final explanation of clear source algorithms should state the starting state, the governing rule, the ordered outcome and one boundary. It should not depend on a screenshot, one software message or an unstated assumption. That form is short enough for revision and precise enough for a reproducible technical note.
The short answer is that ReadableStreamError stores the reported reason and uses it for pending and later consumer failures. Chapter 7 focuses on store the producer reason. Begin with keep controller state, pending pull-into descriptors, bytes filled, queue entries, queueTotalSize, current BYOB request, stored error, read-into requests and reader.closed settlement in separate columns. Writing those facts first prevents a familiar label or final summary value from replacing the mechanism or measurement basis that actually decides the result.
Worked example. report the same Error object E and compare read rejection with reader.closed rejection identity. Treat every stated value as part of a controlled teaching fixture. Record the starting state before the operation, then record each conversion, selection, calculation, check or state transition in order. If a prerequisite fails, stop the trace there rather than inferring later effects from the usual path.
A useful first-principles question for store the producer reason is: what must already be true before this step can run? Use the rule above to separate the input contract from the result. Follow object identity, state and returned value independently. Two branches can print similar data while differing in ownership, timing, brand or future capability.
Now change exactly one premise. report a string reason in a separate fixture and preserve that exact value. Recalculate the trace from the changed fact rather than editing the old conclusion. Name the earliest event that differs, carry that difference through the remaining steps, and say which observations stay the same because their prerequisites did not change.
The main limit is this: applications may wrap errors later, so the fixture must observe the stream promises directly. Keep language semantics separate from processor strategy, host scheduling, browser support, trust policy and the meaning assigned by an application. A focused example can establish the stated mechanism without pretending to settle those broader questions.
Practical evidence check. check strict identity or exact primitive equality at each rejection. Capture the reported values and failure conditions, but also preserve the calculation or event trail that led to them. A check that asserts only the last number or label can pass even when an earlier selection, conversion, grouping, state change or measurement basis was wrong.
A concise final explanation of store the producer reason should state the starting state, the governing rule, the ordered outcome and one boundary. It should not depend on a screenshot, one software message or an unstated assumption. That form is short enough for revision and precise enough for a reproducible technical note.
The short answer is that the pending BYOB read rejects rather than closing with an empty or short view when the stream errors. Chapter 8 focuses on reject the read-into request. Begin with keep controller state, pending pull-into descriptors, bytes filled, queue entries, queueTotalSize, current BYOB request, stored error, read-into requests and reader.closed settlement in separate columns. Writing those facts first prevents a familiar label or final summary value from replacing the mechanism or measurement basis that actually decides the result.
Worked example. await the read promise and capture device-fault without a value or done result. Treat every stated value as part of a controlled teaching fixture. Record the starting state before the operation, then record each conversion, selection, calculation, check or state transition in order. If a prerequisite fails, stop the trace there rather than inferring later effects from the usual path.
A useful first-principles question for reject the read-into request is: what must already be true before this step can run? Use the rule above to separate the input contract from the result. Follow object identity, state and returned value independently. Two branches can print similar data while differing in ownership, timing, brand or future capability.
Now change exactly one premise. replace error with ordinary close after aligned partial data and follow the different close settlement. Recalculate the trace from the changed fact rather than editing the old conclusion. Name the earliest event that differs, carry that difference through the remaining steps, and say which observations stay the same because their prerequisites did not change.
The main limit is this: error and end-of-stream are terminal states with different evidence. Keep language semantics separate from processor strategy, host scheduling, browser support, trust policy and the meaning assigned by an application. A focused example can establish the stated mechanism without pretending to settle those broader questions.
Practical evidence check. assert promise branch, rejection reason and absence of a fulfilled view. Capture the reported values and failure conditions, but also preserve the calculation or event trail that led to them. A check that asserts only the last number or label can pass even when an earlier selection, conversion, grouping, state change or measurement basis was wrong.
A concise final explanation of reject the read-into request should state the starting state, the governing rule, the ordered outcome and one boundary. It should not depend on a screenshot, one software message or an unstated assumption. That form is short enough for revision and precise enough for a reproducible technical note.
The short answer is that a view committed before error remains a completed result even though the next read and reader.closed reject. Chapter 9 focuses on preserve earlier committed results. Begin with keep controller state, pending pull-into descriptors, bytes filled, queue entries, queueTotalSize, current BYOB request, stored error, read-into requests and reader.closed settlement in separate columns. Writing those facts first prevents a familiar label or final summary value from replacing the mechanism or measurement basis that actually decides the result.
Worked example. commit bytes 1 through 4, issue read two, then error before new bytes arrive. Treat every stated value as part of a controlled teaching fixture. Record the starting state before the operation, then record each conversion, selection, calculation, check or state transition in order. If a prerequisite fails, stop the trace there rather than inferring later effects from the usual path.
A useful first-principles question for preserve earlier committed results is: what must already be true before this step can run? Use the rule above to separate the input contract from the result. Follow object identity, state and returned value independently. Two branches can print similar data while differing in ownership, timing, brand or future capability.
Now change exactly one premise. move the error before the first commit and show that neither read fulfils. Recalculate the trace from the changed fact rather than editing the old conclusion. Name the earliest event that differs, carry that difference through the remaining steps, and say which observations stay the same because their prerequisites did not change.
The main limit is this: stream failure cannot retroactively withdraw values already returned. Keep language semantics separate from processor strategy, host scheduling, browser support, trust policy and the meaning assigned by an application. A focused example can establish the stated mechanism without pretending to settle those broader questions.
Practical evidence check. number settlements and keep historical results separate from current state. Capture the reported values and failure conditions, but also preserve the calculation or event trail that led to them. A check that asserts only the last number or label can pass even when an earlier selection, conversion, grouping, state change or measurement basis was wrong.
A concise final explanation of preserve earlier committed results should state the starting state, the governing rule, the ordered outcome and one boundary. It should not depend on a screenshot, one software message or an unstated assumption. That form is short enough for revision and precise enough for a reproducible technical note.
The short answer is that calling error after the stream is no longer readable returns without replacing its established terminal state. Chapter 10 focuses on ignore repeated terminal reports. Begin with keep controller state, pending pull-into descriptors, bytes filled, queue entries, queueTotalSize, current BYOB request, stored error, read-into requests and reader.closed settlement in separate columns. Writing those facts first prevents a familiar label or final summary value from replacing the mechanism or measurement basis that actually decides the result.
Worked example. error with E1 and then call error with E2 while observing later reads. Treat every stated value as part of a controlled teaching fixture. Record the starting state before the operation, then record each conversion, selection, calculation, check or state transition in order. If a prerequisite fails, stop the trace there rather than inferring later effects from the usual path.
A useful first-principles question for ignore repeated terminal reports is: what must already be true before this step can run? Use the rule above to separate the input contract from the result. Follow object identity, state and returned value independently. Two branches can print similar data while differing in ownership, timing, brand or future capability.
Now change exactly one premise. close the stream first and then attempt error E2. Recalculate the trace from the changed fact rather than editing the old conclusion. Name the earliest event that differs, carry that difference through the remaining steps, and say which observations stay the same because their prerequisites did not change.
The main limit is this: the first terminal transition determines the consumer-visible state for this fixture. Keep language semantics separate from processor strategy, host scheduling, browser support, trust policy and the meaning assigned by an application. A focused example can establish the stated mechanism without pretending to settle those broader questions.
Practical evidence check. record state before each call and the final stored reason. Capture the reported values and failure conditions, but also preserve the calculation or event trail that led to them. A check that asserts only the last number or label can pass even when an earlier selection, conversion, grouping, state change or measurement basis was wrong.
A concise final explanation of ignore repeated terminal reports should state the starting state, the governing rule, the ordered outcome and one boundary. It should not depend on a screenshot, one software message or an unstated assumption. That form is short enough for revision and precise enough for a reproducible technical note.
The short answer is that byte-controller cleanup is the same controller action, but a default read request rejects without a consumer pull-into view. Chapter 11 focuses on test a default-reader contrast. Begin with keep controller state, pending pull-into descriptors, bytes filled, queue entries, queueTotalSize, current BYOB request, stored error, read-into requests and reader.closed settlement in separate columns. Writing those facts first prevents a familiar label or final summary value from replacing the mechanism or measurement basis that actually decides the result.
Worked example. run matched BYOB and default-reader pending reads against one fault sequence. Treat every stated value as part of a controlled teaching fixture. Record the starting state before the operation, then record each conversion, selection, calculation, check or state transition in order. If a prerequisite fails, stop the trace there rather than inferring later effects from the usual path.
A useful first-principles question for test a default-reader contrast is: what must already be true before this step can run? Use the rule above to separate the input contract from the result. Follow object identity, state and returned value independently. Two branches can print similar data while differing in ownership, timing, brand or future capability.
Now change exactly one premise. enable autoAllocateChunkSize for the default reader and identify its internal descriptor without calling it consumer BYOB. Recalculate the trace from the changed fact rather than editing the old conclusion. Name the earliest event that differs, carry that difference through the remaining steps, and say which observations stay the same because their prerequisites did not change.
The main limit is this: returned reader API and internal buffer machinery must not be conflated. Keep language semantics separate from processor strategy, host scheduling, browser support, trust policy and the meaning assigned by an application. A focused example can establish the stated mechanism without pretending to settle those broader questions.
Practical evidence check. compare reader type, descriptor type, rejected promise and exposed view. Capture the reported values and failure conditions, but also preserve the calculation or event trail that led to them. A check that asserts only the last number or label can pass even when an earlier selection, conversion, grouping, state change or measurement basis was wrong.
A concise final explanation of test a default-reader contrast should state the starting state, the governing rule, the ordered outcome and one boundary. It should not depend on a screenshot, one software message or an unstated assumption. That form is short enough for revision and precise enough for a reproducible technical note.
The short answer is that a complete receipt orders descriptor clearing, queue reset, algorithm clearing, stream error and promise rejection. Chapter 12 focuses on build an error-cleanup receipt. Begin with keep controller state, pending pull-into descriptors, bytes filled, queue entries, queueTotalSize, current BYOB request, stored error, read-into requests and reader.closed settlement in separate columns. Writing those facts first prevents a familiar label or final summary value from replacing the mechanism or measurement basis that actually decides the result.
Worked example. trace one partial descriptor, one queued remainder and Error E through the full sequence. Treat every stated value as part of a controlled teaching fixture. Record the starting state before the operation, then record each conversion, selection, calculation, check or state transition in order. If a prerequisite fails, stop the trace there rather than inferring later effects from the usual path.
A useful first-principles question for build an error-cleanup receipt is: what must already be true before this step can run? Use the rule above to separate the input contract from the result. Follow object identity, state and returned value independently. Two branches can print similar data while differing in ownership, timing, brand or future capability.
Now change exactly one premise. change only the timing so a first view commits before E and predict the preserved result. Recalculate the trace from the changed fact rather than editing the old conclusion. Name the earliest event that differs, carry that difference through the remaining steps, and say which observations stay the same because their prerequisites did not change.
The main limit is this: the receipt proves stream semantics for the fixture rather than external device recovery. Keep language semantics separate from processor strategy, host scheduling, browser support, trust policy and the meaning assigned by an application. A focused example can establish the stated mechanism without pretending to settle those broader questions.
Practical evidence check. verify no byte is reported twice, no stale request is usable and every pending promise settles once. Capture the reported values and failure conditions, but also preserve the calculation or event trail that led to them. A check that asserts only the last number or label can pass even when an earlier selection, conversion, grouping, state change or measurement basis was wrong.
A concise final explanation of build an error-cleanup receipt should state the starting state, the governing rule, the ordered outcome and one boundary. It should not depend on a screenshot, one software message or an unstated assumption. That form is short enough for revision and precise enough for a reproducible technical note.
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Frequently asked questions
Does error return a short BYOB view?
No. The pending read rejects; a short view belongs to valid closure rules, not producer error.
What happens to partially filled bytes?
They are cleared with the pending pull-into state and are not delivered later.
Are queued bytes preserved?
No. The controller queue is reset when the byte stream is errored.
Which error reaches the reader?
The reason used to error the stream is stored and used for pending or later failures.
Can a previous read stay fulfilled?
Yes. A result committed before the error remains settled.
What should a test record?
Descriptor state, queue state, stored error, each read settlement and reader.closed.
Continue through the verified reading routes
Start with the wider system
The Gold Standard of Websites · The Gold Standard of Education | Learning That Transfers into Life · How X Works hub
Compare the closest mechanisms
The Gold Standard of Websites | Separating ReadableStream Cancellation from Producer-Reported Errors · The Gold Standard of Websites | Tracing ReadableStream BYOB Minimum Fill and View Detachment · The Gold Standard of Websites | Separating BYOB respond Byte Counts from respondWithNewView View Replacement · The Gold Standard of Websites | Separating ReadableByteStreamController enqueue from Fulfilling a Live BYOB Request · The Gold Standard of Websites | Tracing BYOB Reader Release with a Partially Filled Pull-Into Descriptor · The Gold Standard of Websites | Separating TransformStream Controller Termination from Controller-Reported Errors · The Gold Standard of Websites | Separating Queuing-Strategy Size Callback Failure from Backpressure Caused by a Large Valid Size
Choose the next lesson by reader job
Use the subject root to move from this focused mechanism to the next verified question. Follow a specialist link when its preconditions match your code; return to the wider hub when the next task belongs to a different system.
Authoritative sources and evidence checks
WHATWG Streams Living Standard · WHATWG Streams — readable byte stream controllers · WHATWG Streams — pull-into descriptors · WHATWG Streams source repository
The normative mechanism follows the WHATWG Streams Living Standard, last updated 25 October 2026 when checked for this article. The worked buffers, queues, promise settlements and callback logs are original teaching fixtures. They establish the specified stream behavior; they do not claim network delivery, storage durability or application acceptance.