<S extends Schema.ConstraintDecoder<unknown>>(
schema: S,
options?: SchemaAST.ParseOptions
): (
input: unknown,
options?: SchemaAST.ParseOptions
) => Result.Result<S["Type"], SchemaIssue.Issue>Creates a decoder for unknown input that reports failure safely as a
Result.
When to use
Use when decoding untyped boundary input and you want SchemaIssue.Issue
failures returned as data in a Result.
Details
The returned function produces Result.succeed with the decoded Type on
success or Result.fail with a SchemaIssue.Issue on decoding failure.
Gotchas
This adapter runs synchronously. Causes made entirely of schema issues become
Result.fail, but causes that contain defects, interruptions, or asynchronous
work at this synchronous boundary throw instead.
export function function decodeUnknownResult<
S extends Schema.ConstraintDecoder<unknown>
>(
schema: S,
options?: SchemaAST.ParseOptions
): (
input: unknown,
options?: SchemaAST.ParseOptions
) => Result.Result<S["Type"], SchemaIssue.Issue>
Creates a decoder for unknown input that reports failure safely as a
Result.
When to use
Use when decoding untyped boundary input and you want SchemaIssue.Issue
failures returned as data in a Result.
Details
The returned function produces Result.succeed with the decoded Type on
success or Result.fail with a SchemaIssue.Issue on decoding failure.
Gotchas
This adapter runs synchronously. Causes made entirely of schema issues become
Result.fail, but causes that contain defects, interruptions, or asynchronous
work at this synchronous boundary throw instead.
decodeUnknownResult<function (type parameter) S in decodeUnknownResult<S extends Schema.ConstraintDecoder<unknown>>(schema: S, options?: SchemaAST.ParseOptions): (input: unknown, options?: SchemaAST.ParseOptions) => Result.Result<S["Type"], SchemaIssue.Issue>S extends import SchemaSchema.interface ConstraintDecoder<out T, out RD = never>Lightweight structural constraint for APIs that need decoder type views but
do not need the full schema protocol.
When to use
Use when you need to preserve a schema's decoded type and decoding services,
but the API does not constrain the encoded type, encoding services, or call
schema methods such as annotate, check, rebuild, make, or
makeEffect.
ConstraintDecoder<unknown>>(
schema: S extends Schema.ConstraintDecoder<unknown>schema: function (type parameter) S in decodeUnknownResult<S extends Schema.ConstraintDecoder<unknown>>(schema: S, options?: SchemaAST.ParseOptions): (input: unknown, options?: SchemaAST.ParseOptions) => Result.Result<S["Type"], SchemaIssue.Issue>S,
options: SchemaAST.ParseOptionsoptions?: import SchemaASTSchemaAST.ParseOptions
): (input: unknowninput: unknown, options: SchemaAST.ParseOptionsoptions?: import SchemaASTSchemaAST.ParseOptions) => import ResultResult.type Result<A, E = never> = Result.Success<A, E> | Result.Failure<A, E>A value that is either Success<A, E> or Failure<A, E>.
When to use
Use when both success and failure should remain available as data and
Option would lose failure information.
Details
- Use
succeed
/
fail
to construct
- Use
match
to fold both branches
- Use
isSuccess
/
isFailure
to narrow the type
E defaults to never, so Result<number> means a result that cannot fail.
Example (Creating and matching a Result)
import { Result } from "effect"
const success = Result.succeed(42)
const failure = Result.fail("something went wrong")
const message = Result.match(success, {
onSuccess: (value) => `Success: ${value}`,
onFailure: (error) => `Error: ${error}`
})
console.log(message)
// Output: "Success: 42"
Namespace containing type-level utilities for extracting the inner types
of a Result.
Example (Extracting inner types)
import type { Result } from "effect"
type R = Result.Result<number, string>
// number
type A = Result.Result.Success<R>
// string
type E = Result.Result.Failure<R>
Result<function (type parameter) S in decodeUnknownResult<S extends Schema.ConstraintDecoder<unknown>>(schema: S, options?: SchemaAST.ParseOptions): (input: unknown, options?: SchemaAST.ParseOptions) => Result.Result<S["Type"], SchemaIssue.Issue>S["Type"], import SchemaIssueSchemaIssue.type Issue =
| SchemaIssue.Leaf
| SchemaIssue.Filter
| SchemaIssue.Encoding
| SchemaIssue.Pointer
| SchemaIssue.Composite
| SchemaIssue.AnyOf
The root discriminated union of all validation error nodes.
When to use
Use when typing the error channel in Effect<A, Issue, R> results from
schema parsing, or when writing custom formatters or issue-tree walkers.
Details
Every node has a _tag field for pattern-matching. The union includes both
terminal
Leaf
types and composite types that wrap inner issues:
Filter
,
Encoding
,
Pointer
,
Composite
,
AnyOf
. All Issue instances have a toString() that delegates to
the default formatter, so String(issue) produces a human-readable message.
Issue> {
return function asResult<T, E, R>(
parser: (
input: E,
options?: SchemaAST.ParseOptions
) => Effect.Effect<T, SchemaIssue.Issue, R>
): (
input: E,
options?: SchemaAST.ParseOptions
) => Result.Result<T, SchemaIssue.Issue>
function decodeUnknownEffect<
S extends Schema.Constraint
>(
schema: S,
options?: SchemaAST.ParseOptions
): (
input: unknown,
options?: SchemaAST.ParseOptions
) => Effect.Effect<
S["Type"],
SchemaIssue.Issue,
S["DecodingServices"]
>
Creates an effectful decoder for unknown input.
When to use
Use when you need to decode untyped boundary input in an Effect whose
failure channel is SchemaIssue.Issue, while preserving transformations
and service requirements.
Details
The returned function succeeds with the schema's decoded Type or fails with a
SchemaIssue.Issue. Decoding service requirements are preserved in the returned
Effect. Parse options may be provided when creating the decoder and overridden
when applying it.
decodeUnknownEffect(schema: S extends Schema.ConstraintDecoder<unknown>schema, options: SchemaAST.ParseOptionsoptions))
}