API | Lambda Prelude

The full method-level reference for built-in classes and the standard library ships with each release for NDA partners. The page below summarises which classes exist and points to the relevant example files.

Core

Array and String use 1-based indexing per Smalltalk convention for at: / at:put: / indexOf: / copyFrom:to: and related index-bearing methods; at: 1 is the first element.

Class	Notes
`Integer`, `Float`	Standard arithmetic, `factorial`, `negated`, `timesRepeat:`, `to:`, `to:do:`, bit ops, comparisons (`min:` / `max:` via `Comparable`)
`Boolean`, `True`, `False`	`ifTrue:`, `ifFalse:`, `ifTrue:ifFalse:`, `and:`, `or:`, `not`
`String`	Slicing, `concat:`, `asUppercase`, `asLowercase`, `trimmed`, regex match, `size`, `at:`, `lines`, `replaceAll:with:`, `<`
`Char`	Character predicates and conversion
`Regex`	`compile:`, then `match:`, `matches:`, `findAll:`, `replaceAll:with:`, `split:` (the `String` regex helpers dispatch through this)
`DateTime`	`now`, `parse:`, `fromMs:`, `y:m:d:h:min:s:` (+ `ms:`), `formattedAs:`, `isoString`, and `year` … `millisecond` field accessors (millisecond precision)
`Error`	`Error raise:` to signal, `Error try:onError:` to catch — the handler receives the message string (no exception-type hierarchy)
`Array`	Persistent 32-way trie, `with:`, `at:`, `at:put:`, `size`, `do:`, `collect:`, `select:`, `inject:into:`, `sort:`, `indexOf:`, `,`
`Dict`	Persistent HAMT, `new`, `from:`, `at:`, `at:put:`, `at:ifAbsent:`, `at:ifPresent:ifAbsent:`, `includesKey:`, `keys`, `size`, `associations`, iteration
`Set`	Built on Array
`Maybe`	Parameterised absence type, `none`, `some:`, `ifPresent:ifAbsent:`, `isPresent`
`Block`	`value`, `value:`, `value:value:`, ... `valueWithArguments:`, `whileTrue:`
`Class`	Class meta-operations, reflection
`Object`	`printNl`, `print`, `=`, `~=`, `asString`, `printOn:`, `className`, `isKindOf:`, `fieldNames`, `atField:`, `atField:put:`, `asObject`, `perform:`, `perform:withArgs:`
`WriteStream`	`<<` dispatching through `printOn:`, `nl`, `space`, `tab`, `position`, `isEmpty`, `reset`
`Comparable`, `Enumerable`	Protocol-bound mixins (`Enumerable` includes `detect:` / `anySatisfy:` / `min` / `max`)

Actor and Concurrency

Class	Notes
`Actor`	`self`, `spawn:`, `!`, `receive`, `receive:`, `receive:after:do:`, `ask:`, `monitor:`, `linkTo:`, `trapExits:`
`Future`	`await`, `await:`, `resolved?`, `pending?`, `resolve:`, `fail:`, `new` (manual construction)
`Down`, `Exit`	Monitor / link failure envelopes carrying actor ref + reason

Service Layer

Class	Notes
`HTTP`, `HttpServer`, `HttpResponse`, `HttpRequest`	HTTP server takes a block as handler; chunked + keepalive supported; `HTTP parseMultipart:boundary:` → `MultipartPart` (`name` / `filename` / `contentType` / `bytes`) for file uploads
`LpHttpClient`	HTTP client — `get:retries:`, `post:body:contentType:retries:` → `HttpResponse`
`TCP`, `TCPSocket`, `TCPServer`	Bounded socket I/O integrated with the actor scheduler
`TLS`, `TLSSocket`	`Tls.Engine` driven, handshake / read / write park on I/O wait
`UDP`, `UDPSocket`, `UDPDatagram`	datagram sockets — `bind:` / `bindHost:port:`, `sendTo:port:data:`, `receiveFrom` / `receiveFrom:`; a received `UDPDatagram` carries the source `host` / `port` for replies
`WebSocket`	`accept:on:`, `isUpgrade:`, `readFrame:`, `writeText:to:`, `writeBinary:to:`, `writePong:to:`, `writeClose:`
`JSON`	`parse:`, `serialize:`
`JsonRpcServer`, `JsonRpcClient`	JSON-RPC 2.0 dispatch — single, batch, notifications, error envelopes
`Remote`	`Remote at:for:id:` — proxy to a remote class over JSON-RPC; typed against the target class's protocol when built with a literal class (a non-literal `for:` stays dynamically typed)
`TeriosServer`, `ServiceDispatcher`, `Res`	TERIOS-style `serviceName` / `requestDto` / `responseDto` / `errorInfoList` envelopes

Runtime

Class	Notes
`File`	`read:`, `write:contents:`, `delete:`, `exists:`, `mkdirP:`, `rename:to:`, `listDir:`, `isDir:`, `isFile:`
`OS`	`stdinLine`, `stdinAll`, `stdinPasswordLine` (suppresses echo on Windows console + POSIX TTYs), `hostname`, env vars with defaults; subprocess & watchdog — `exec:` / `exec:input:`, fire-and-forget `spawn:` / `spawn:output:`, `running:` liveness probe, `kill:`, `gracefulShutdown:`
`Log`	Structured logging (`info:`, `warn:`, `error:`, key-value fields)

Data

Class	Notes
`DB`, `DBConnection`	SQLite (built in) — `open:`, `exec:`, `exec:params:`, `query:`, `query:params:`, `close`
`Postgres`, `PostgresConnection`	PostgreSQL via `Dynlink` plugin (interpreter / AOT)
`Mariadb`, `MariadbConnection`	MariaDB / MySQL via `Dynlink` plugin (interpreter / AOT)
`Redis`, `RedisConnection`	Redis / Valkey via `Dynlink` plugin (RESP2 over scheduler-integrated non-blocking TCP), `ping` / `get:` / `set:value:` / `set:value:ex:` / `del:` / `incr:` / `decr:` / `exists:` / `expire:seconds:` / `keys:` / `auth:` / `multi` / `exec` / `discard` / `cmd:` / `close`
`TORM`	Doma-compatible 2-way SQL templates + DAO / Entity macro DSL (`dao:` / `entity:` keywords)

Crypto

Class	Notes
`Hash`	SHA-256, SHA-512, HMAC-SHA-256 (`hmacSha256:key:`)
`Aes`	AES-256-GCM
`Argon2`	Argon2id password KDF (RFC 9106), backed by system libargon2
`JWT`	Sign / verify
`Random`	`Random hex:` — random hex string

Operations

Class	Notes
`LpCache`	In-memory cache builtin with size / TTL bounds (`start:`, `at:`, `at:put:`, `at:put:ttl:`)
`LpChannel`	In-process pub/sub. `subscribe:do:` / `publish:message:` / `subscriberCount`
`Supervisor`	One-for-one / one-for-all / rest-for-one strategies on top of monitor + spawn
`Metric`	Named in-memory counters for service-level instrumentation
`Test`	`run:do:`, `assert:`, `assert:message:`, `assertEqual:to:`, `fail:`, `summary`

Standard Library Modules

These ship as .lp files under stdlib/ and are loaded with module Main imports: (...). The standard library stays intentionally small; the modules below are the full set.

Core protocols

comparable.lp — Comparable protocol with <-based defaults (>, min:, max:, ...)
enumerable.lp — Enumerable protocol with do:-based defaults (collect:, select:, inject:into:, ...)
set.lp — persistent Set backed by Array, add: / remove: / includes:
ordered_dict.lp — Dict variant that preserves insertion order on iteration
association.lp — (key, value) pair object; element type of Dict>>associations / Dict>>associationsDo:

Service runtime

http.lp — accept loop and keep-alive aware connection handler on top of the HTTP builtin
json_rpc.lp — JSON-RPC 2.0 server and client over HTTP (single / batch / notification / error)
lp_server.lp — one-line exposure of an LP service as a JSON-RPC 2.0 endpoint
sse.lp — Server-Sent Events writer on top of HTTP/1.1 chunked
cache.lp — actor-owned KV cache with capacity (LRU) and optional TTL
grain.lp — virtual actors (grains): GrainServer / GrainStore / RedisGrainStore, directory + owner + lease single-activation, cross-node leasing with a fence token, pluggable store

Connection pools (Dynlink plugins — interpreter / AOT)

postgres_pool.lp — fixed-size pool over the postgres plugin, withConn: API
mariadb_pool.lp — fixed-size pool over the mariadb plugin (MariaDB / MySQL)
redis_pool.lp — fixed-size pool over the redis plugin (Redis / Valkey)

Supervision

supervision.lp — one-for-one / one-for-all / rest-for-one strategies on monitor: + spawn:

TERIOS toolkit (`stdlib/terios/`)

terios/rpc.lp — TERIOS RPC envelope dispatch (serviceName / requestDto / responseDto / errorInfoList)
terios/auth.lp — bearer-token auth scaffold + HTTP middleware
terios/transformer.lp — declarative JSON reshaping engine (DataTransformer port)
terios/validators.lp — declarative validators for the validates: class-decl keyword

TORM toolkit (`stdlib/torm/`)

torm/entity_listener.lp — EntityListener protocol with prePersist: / postLoad: style hooks
torm/select_options.lp — Doma-style immutable SELECT options (paging / lock hints)