Hacktoberfest 2026: los issues que los mantenedores marcaron para octubre, abiertos y aptos para principiantes. Explorar issues de Hacktoberfest

Schema: idiomatic way to encode against a type-erased `Schema.Top` (codec services show as `unknown` in the requirements channel)?

Abierto
  • ¿Algo no está bien?
#6,489 1 comentario 0 reacciones 0 asignados Ver en GitHub

Los mantenedores suelen responder en 1 día

Nadie ha tomado este issue todavía.

Evaluación

Dificultad
5/5
Tiempo estimado
Más de una semana
Aptitud para principiantes
35/100
Tipo de issue
Nueva funcionalidad
Claridad
Bastante claro
Estado de actividad
Tranquilo
Stack tecnológico
typescript
Área
api

Línea de trabajo

Start with the Schema.Top, Schema.toCodecJson, Schema.encodeUnknownEffect, encodeUnknownExit, and encodeUnknownResult APIs, then run the linked reproduction with bun install and bun run repro. Compare the reported R=unknown and R=never assertions and runtime check; done would require an agreed idiomatic way to encode or decode service-free type-erased schemas without an unsafe cast.

Escrito por el modelo de indexación a partir del texto del issue.

Descripción

This is a usage/idiom question about encoding against type-erased schemas.

When you only have a type-erased Schema.Top — e.g. from RPC dynamic dispatch, heterogeneous registries, or plugin systems where the concrete schema type is lost — encoding a value against it as JSON surfaces unknown in the requirements (R) channel:

declare const erased: Schema.Top
const eff = Schema.encodeUnknownEffect(Schema.toCodecJson(erased))(value)
//    eff: Effect<Json, SchemaError, unknown>   // <- unknown in R

Schema.Top types DecodingServices/EncodingServices as unknown, and toCodecJson + encodeUnknownEffect forward them into R. @effect/language-service flags it as anyUnknownInErrorContext (TS377030, "unknown in the requirements channel"). But such schemas are plain data — they need no codec services (the repro verifies this at runtime).

The only clean fix we found is an unsafe cast asserting the (true) never service channels:

Schema.toCodecJson(erased as Schema.Codec<unknown, unknown, never, never>)
//    -> Effect<Json, SchemaError, never>

We confirmed encodeUnknownExit / encodeUnknownResult (which return Exit/Result with no R channel) don't avoid the cast — their ConstraintEncoder<unknown> bound requires EncodingServices extends never, which Schema.Top doesn't satisfy.

Question: is casting the service channels the idiomatic way to encode/decode against a Schema.Top known to need no services, or is there a cleaner, more Effect-native API for this (a service-erasing combinator, an encode variant that ignores services, a better way to type-erase RPC schemas, etc.)?

Reproduction

https://github.com/schickling-repros/2026-07-effect-erased-schema-services

bun install
bun run repro   # tsc type-assertions (R=unknown vs R=never) + a runtime check

Versions

  • effect: 4.0.0-beta.98
  • @effect/language-service: anyUnknownInErrorContext (TS377030)

Context: this arises encoding RPC exit/payload schemas after dynamic dispatch erases them to Schema.Top — a follow-on to #6064 (which exposed successSchema but not the service-typing question).

Posted on behalf of @schickling
field value
agent_name 🌲 cl1-pine
agent_session_id b9f1f4a5-dd10-40f6-b25c-945e71e2007a
agent_tool Claude Code
agent_tool_version 2.1.206
agent_runtime Claude Code 2.1.206
agent_model claude-opus-4-8
runtime_profile /nix/store/1n76sy6i9y3ki3k4w04jksqvygw67sj0-coding-agent-runtime-profile/share/coding-agents/profile.json
skills_manifest /nix/store/jn6r0r7r59x3a525jch4pwzwykszqp60-agent-skills-corpus/share/agent-skills/manifest.json
worktree livestore/schickling/2026-07-17-refactor
machine dev3
tooling_profile dotfiles@4eac376
Lenguaje dominante
TypeScript
Estrellas
16.7k
Forks
808
Merge medio
10 h 33 min
PR fusionados (30 d)
830

Preparar el entorno

Este proyecto no incluye contenedor de desarrollo, Dockerfile ni guía de contribución, así que la configuración corre por tu cuenta: empieza por su README y consulta nuestra guía para la primera contribución para los pasos generales.

Primeros pasos

  1. Lee el issue completo y luego la guía de contribución del proyecto.
  2. Comenta en el issue que vas a ocuparte — evita que dos personas hagan lo mismo.
  3. Haz un fork del repositorio y trabaja en una rama.
  4. Abre un pull request que haga referencia al número del issue.

Más de Effect-TS/effect

Todos los issues de Effect-TS/effect

Issues similares

Más issues de TypeScript

Recibe los nuevos issues en tu correo

Un resumen breve de issues de GitHub para principiantes.