(name?: string): Config<string>Creates a config for a single string value.
When to use
Use when reading a single string env var or config key.
Details
Shortcut for Config.schema(Schema.String, name).
Example (Reading a string config)
import { Config, ConfigProvider, Effect } from "effect"
const host = Config.string("HOST")
const provider = ConfigProvider.fromUnknown({ HOST: "localhost" })
// Effect.runSync(host.parse(provider)) // "localhost"export function function string(
name?: string
): Config<string>
Creates a config for a single string value.
When to use
Use when reading a single string env var or config key.
Details
Shortcut for Config.schema(Schema.String, name).
Example (Reading a string config)
import { Config, ConfigProvider, Effect } from "effect"
const host = Config.string("HOST")
const provider = ConfigProvider.fromUnknown({ HOST: "localhost" })
// Effect.runSync(host.parse(provider)) // "localhost"
string(name: string | undefinedname?: string) {
return function schema<T>(
codec: Schema.ConstraintCodec<T, unknown>,
path?: string | ConfigProvider.Path
): Config<T>
Creates a Config<T> from a Schema.Codec.
When to use
Use when you need to read structured or schema-validated configuration.
Details
The optional path sets the local path segment(s) for the config lookup.
It is appended to the logical path prefix accumulated from outer
nested
calls. Pass a single string for a flat key or an array for
nested paths.
Convenience constructors such as string, number, and boolean delegate
to this API.
The codec is used to decode the raw StringTree produced by the provider
into T. Schema validation errors are wrapped in ConfigError.
Example (Reading a structured config)
import { Config, ConfigProvider, Effect, Schema } from "effect"
const DbConfig = Config.schema(
Schema.Struct({
host: Schema.String,
port: Schema.Int
}),
"db"
)
const provider = ConfigProvider.fromUnknown({
db: { host: "localhost", port: 5432 }
})
// Effect.runSync(DbConfig.parse(provider))
// { host: "localhost", port: 5432 }
schema(import SchemaSchema.const String: Stringconst String: {
Rebuild: Rebuild;
Iso: Iso;
ast: Ast;
Type: T;
Encoded: E;
DecodingServices: RD;
EncodingServices: RE;
annotate: (annotations: Schema.Annotations.Bottom<string, readonly []>) => Schema.String;
annotateKey: (annotations: Schema.Annotations.Key<string>) => Schema.String;
check: (checks_0: SchemaAST.Check<string>, ...checks: Array<SchemaAST.Check<string>>) => Schema.String;
rebuild: (ast: SchemaAST.String) => Schema.String;
make: (input: string, options?: MakeOptions) => string;
makeOption: (input: string, options?: MakeOptions) => Option_.Option<string>;
makeEffect: (input: string, options?: MakeOptions) => Effect.Effect<string, SchemaError, never>;
pipe: { <A>(this: A): A; <A, B = never>(this: A, ab: (_: A) => B): B; <A, B = never, C = never>(this: A, ab: (_: A) => B, bc: (_: B) => C): C; <A, B = never, C = never, D = never>(this: A, ab: (_: A) => B, bc: (_: B) => C, cd: (_: C) => D): D; <…;
}
Type-level representation of
String
.
Schema for string values. Validates that the input is typeof "string".
String, name: string | undefinedname)
}