API reference

Every export of @boarteam/fix 0.5.2 — all 98 of them. Generated from the installed package's type declarations — signatures and doc text are the library's own, never paraphrased. A symbol this page misdescribes is a build failure, not a doc bug. The groups mirror the guides, so how-to and what-is stay neighbours.

By area

Engine & constants5 exports — The dictionary-bound engine façade — parse, validate, encode and the typed message builder behind one binding — plus the package's exported constants.Parsing17 exports — From raw bytes to structure: the parser and its result shapes, the lexical tokenizers underneath it, frame splitting for multi-message buffers, and per-value datatype coercion.Validation & issues9 exports — Dictionary conformance as data: the validator, the FixIssue shape every analysis entry point returns, the stable issue-code catalogue, and the conditional-rule extension point.Encoding7 exports — From a tag-keyed message to a framed wire string in dictionary order, plus the byte-accurate framing math — BodyLength and CheckSum over UTF-8 bytes.Typed messages14 exports — The self-rendering Message object: mutable and immutable builders, the init and envelope shapes, the factory the dict packages re-export, and the type guard for narrowing at boundaries.Dictionaries21 exports — The DictionaryJSON data contract and its runtime index, structural validation, and the FIXT.1.1 transport/application pair with its runtime merge.Dictionary extensions25 exports — Venue-specific additions as one declaration: the extension schema, the runtime merge that applies it, and the literal-typed map helpers that keep Tags.SymbolName hovering as 1007.

All exports A–Z

Export	Kind	Summary
BaseType	type	The five root FIX datatypes every other datatype derives from.
bodyLength	function	FIX BodyLength (tag 9): the number of bytes in the message following the BodyLength field's terminating SOH, up to and including the SOH immediately preceding the CheckSum field.
calculateChecksum	function	FIX CheckSum (tag 10): the sum of all bytes of the message — from BeginString up to and including the SOH immediately preceding the checksum field — taken modulo 256 and rendered as a zero-padded three-digit string.
ComponentDef	interface	A reusable component block (e.g.
ComponentExtension	type	A component entry: { members } defines a NEW component; the other form extends an existing one (additions become visible in every referencing scope — deliberate, and reported via extend/component-fanout).
ComponentMember	interface	A reference to a reusable component block; the runtime expands it in place.
ConditionalContext	interface	The read-only view of one message a ConditionalRule reasons over.
ConditionalRule	type	A conditional ("C", required-by-prose) presence rule.
CoverageGap	interface	A note about something the generated dictionary could not fully express, recorded for honest maturity reporting (per the open-source-readiness standard).
createFixEngine	function	Create a FixEngine bound to a dictionary.
createImmutableMessage	function	Create an ImmutableMessage for a MsgType.
createMessage	function	Create a MutableMessage for a MsgType, optionally seeded with a complete MessageInit (omit it to build incrementally).
DataTypeDef	interface	A FIX datatype (e.g.
DecodedValue	type	A FIX field value after datatype coercion: When a value cannot be coerced to its declared type (e.g.
DecodeResult	interface	The result of coercing one wire value: the decoded value plus any diagnostics.
decodeValue	function	Coerce one raw wire value to its typed form per the field's datatype.
DEFAULT_CONDITIONAL_RULES	const	The built-in conditional rules.
defineExtension	function	Pin an extension declaration's literal types once — a zero-cost identity whose TS 5 const type parameter keeps every tag: 1007 / msgType: 'UP1' literal without as const, so the SAME value can drive extendDictionary (runtime) and tagsOf/msgTypesOf (types).
Dictionary	class	A runtime index over a DictionaryJSON: fast lookup of fields, messages, and components, plus the derived structure the codec needs — repeating-group delimiters, component expansion, and per-message allowed-tag sets.
DictionaryExtension	interface	One venue extension declaration — the single source of truth for both layers.
DictionaryJSON	interface	The complete, serializable dictionary.
encode	function	Encode a message into a complete, framed FIX string: fields are emitted in the order the dictionary prescribes for the message (expanding components and repeating groups), then BeginString/BodyLength are prefixed and CheckSum appended.
EncodeMessage	interface	The message to encode.
EncodeOptions	interface	Options for encode.
EngineOptions	interface	Defaults applied to every call, overridable per call.
EnumValue	interface	One allowed value of an enumerated field.
Envelope	interface	Envelope (header/trailer/session) fields supplied to MessageView.render at call time — the fields a Message deliberately does NOT model in its typed body: MsgSeqNum (34), SenderCompID (49), SendingTime (52), TargetCompID (56), and any other standard-header/trailer field.
extendDictionary	function	Apply venue extension declarations to a dictionary, producing a NEW DictionaryJSON the engine consumes unchanged.
extendMsgTypes	function	Merge venue-specific message-type entries over a base MsgType map — the string-valued mirror of extendTags.
ExtendMsgTypes	type	ExtendTags for MsgType maps (name → msgType strings).
ExtendResult	interface	The result of extendDictionary: the merged dictionary plus diagnostics.
extendTags	function	Merge venue-specific tag entries over a base Tags map, keeping every literal type.
ExtendTags	type	The result of extendTags: a key-remapped merge where extension keys cleanly REPLACE base keys.
ExtensionEnumValue	interface	One allowed value to add to a field's enum.
ExtensionFieldDef	interface	A new field.
FieldDef	interface	A FIX field definition, keyed by its numeric tag in DictionaryJSON.fields.
FieldInit	type	A single field/group value in init position: a group-counter value (an array of entry bodies) is accepted as a readonly array of MessageInit-widened entries; scalar values pass through unchanged, so enum unions and dialect casts are preserved.
FieldMember	interface	A plain field reference within a message, component, or group body.
FieldValue	type	A scalar field value the caller can supply.
FixEngine	interface	A dictionary-bound façade over the stateless codec: parse/parseAll/encode/create with the dictionary and default options already applied.
FixIssue	interface	A single diagnostic, returned as data — never thrown — by every analysis entry point (parse, validate, validateDictionary).
FixLayer	type	Which FIXT layer an issue belongs to, when validation ran against a transport/application dictionary pair: session findings are transport-owned (admin messages, envelope fields) and map to a session-level Reject(3); application findings map to a BusinessMessageReject(j).
FixSeverity	type	Severity of a FixIssue.
FixtDictionaries	interface	FIXT support: the transport/application dictionary pair.
FrameOptions	interface	Options for splitMessages and scanFields.
GroupEntry	interface	One entry of a repeating group: its own fields and any nested groups.
GroupExtension	interface	Members to add to one repeating group's entry body.
GroupMember	interface	A repeating group: a NumInGroup counter field (counterTag) followed by as many repetitions of members as the counter's wire value declares.
GuardWidening	type	Compile-time guard: resolves to unknown (no-op) when the extension's tag and msgType literals survived inference, and to WidenedExtensionError when they widened to number/string — which happens when the declaration was pre-typed as DictionaryExtension before the call.
ImmutableMessage	interface	An immutable Message — every edit returns a NEW instance (copy-on-write of the top-level body), leaving the original untouched.
invertMsgTypes	function	Build the msgType → name reverse of a MsgType map — the string-valued mirror of invertTags.
InvertMsgTypes	type	InvertTags for MsgType maps: msgType → name with a string index.
invertTags	function	Build the tag → name reverse of a Tags map, typed as InvertTags: literal lookups for known tags plus the shipped packages' widened name \| undefined number index for arbitrary input.
InvertTags	type	The result of invertTags: the precise tag → name mapped inversion (so TagNames[1007] hovers as its literal name) intersected with the widened index signature the shipped packages use (so TagNames[someNumber] is name \| undefined, never a type error).
isFixtDictionaries	function	Whether a dictionaries argument is the FIXT transport/app pair form.
KnownIssueCode	type	The catalogue of issue codes the engine currently emits.
loadDictionary	function	Build a Dictionary runtime index from its JSON form.
MemberRef	type	A member of a message, component, or group body.
MemberSpec	type	A member to place into a body.
mergeFixtDictionaries	function	Merge a FIXT transport dictionary with an application dictionary into one self-contained DictionaryJSON — the runtime counterpart of the codegen merge that produces @boarteam/fix-dict-fix50sp2, exported for venue-dialect composition (mergeFixtDictionaries(fixt11, myAppLayerDialect)).
MessageCategory	type	A message's session category.
MessageDef	interface	A FIX message definition.
MessageExtension	interface	A patch to an existing message (addressed by name via the record key).
messageFactory	function	Build a dictionary-bound MessageFactory typed by a Bodies registry (the generated MessageBodies map of MsgType value → body type).
MessageFactory	interface	A dictionary-bound, typed message factory — the strongly-typed entry point the dict packages re-export (message).
MessageInit	type	The init shape for a message body B — what MessageFactory, createMessage, and the engine's create accept.
MessageOf	type	The read surface of the message whose MsgType value is M in a Bodies registry — a convenience alias for annotating a narrowed message (a function parameter, a variable).
messageTypeGuard	function	Build a dictionary-agnostic MessageTypeGuard bound to a Bodies registry (the generated MessageBodies map of MsgType value → body type).
MessageTypeGuard	type	A Bodies-bound message-narrowing type guard — the read-side counterpart of MessageFactory.
MessageView	interface	The read surface shared by the mutable and immutable Message — enough to drive log metadata (msgType, Symbol, SecurityID, per-entry prices) and to render to wire.
msgTypesOf	function	Derive the literal name → msgType map of an extension's NEW messages, typed as MsgTypesOf.
MsgTypesOf	type	The literal name → msgType map type derived from an extension's NEW messages (entries carrying msgType); message patches are excluded.
MutableMessage	interface	A mutable, fluent Message builder — the fast path for hot loops (per-tick market-data snapshots): set/assign mutate in place and return this for chaining, then MessageView.render converts the body once.
NewMessageSpec	interface	A brand-new message (the presence of msgType is what marks an entry as new).
parse	function	Parse one FIX message into a structured ParsedMessage with nested repeating groups and coerced field values, returning diagnostics as data.
parseAll	function	Parse every message in a buffer of concatenated frames.
ParsedField	interface	One parsed scalar field.
ParsedGroupEntry	interface	One entry of a repeating group: its own fields and any nested groups, keyed by tag.
ParsedMessage	interface	A parsed FIX message: a structured, nested view of one frame.
ParseOptions	interface	Options for parse and parseAll.
ParseResult	interface	The result of parse: the structured message plus any diagnostics.
Reqd	type	Required-ness of a member: Y required, N optional, C conditional (rule in prose).
ResolvedDatatype	interface	The coercion-relevant facts about a datatype, resolved from its derivation chain by Dictionary.resolveDatatype.
scanFields	function	Tokenize a single message into ordered [tag, value] pairs with length-aware handling of data fields: when a Length field (one that some data field points to via FieldDef.lengthField) is read, the immediately following data field's value is taken as exactly that many UTF-8 bytes — even if it contains the SOH separator — so binary payloads survive intact.
SOH	const	The FIX field separator (SOH, ASCII 0x01).
splitMessages	function	Split a buffer that may hold several concatenated FIX messages into one byte slice per message.
tagsOf	function	Derive the literal name → tag map from an extension declaration, typed as TagsOf.
TagsOf	type	The literal name → tag map type derived from an extension's fields record — TagsOf<typeof ctrader> is { readonly SymbolName: 1007; readonly SymbolDigits: 1008 }.
toEncodeMessage	function	Convert a ParsedMessage back into an EncodeMessage suitable for encode, using each field's verbatim ParsedField.raw value so the round-trip preserves the exact wire content.
Token	type	A single decoded FIX field: its numeric tag and its raw, still-encoded value.
tokenize	function	Split a raw FIX message into ordered [tag, value] pairs.
TokenizeOptions	interface	Options for tokenize.
UntypedBody	type	The loose body type for the untyped path: any field name maps to any scalar value or, for a group counter name, an array of entry bodies.
validate	function	Validate a parsed FIX message against a dictionary, returning diagnostics as data.
validateDictionary	function	Structurally validate a DictionaryJSON: every reference resolves, every field has a known datatype and a valid tag, datatype bases are real roots, group counters are real counter fields with a resolvable delimiter, enum values are unique, and the datatype derivation tree is acyclic.
ValidateOptions	interface	Options for validate.
VERSION	const	@boarteam/fix — a dictionary-driven FIX protocol toolkit.
WidenedExtensionError	interface	The compile error surfaced by GuardWidening when an extension's literals were widened before reaching defineExtension.