API reference / @evolu/common / Type / OptionalType

Interface: OptionalType<T>

Defined in: packages/common/src/Type.ts:3612

Extends

• Type<"Optional", InferType<T>, InferInput<T>, InferError<T>, InferParent<T>, InferParentError<T>>

Type Parameters

Type Parameter
T extends AnyType

Properties

Property	Modifier	Type	Description	Inherited from	Defined in
[EvoluTypeSymbol]	readonly	true	-	Type.[EvoluTypeSymbol]	packages/common/src/Type.ts:167
Error	public	InferError<T>	The specific error introduced by this Type. ### Example type StringError = typeof String.Error;	Type.Error	packages/common/src/Type.ts:92
Errors	readonly	| InferError<T> | InferParentError<T>	Error	ParentError ### Example type StringParentErrors = typeof String.Errors;	Type.Errors
from	readonly	(value) => Result<InferType<T>, | InferError<T> | InferParentError<T>>	Creates T from an Input value. This is useful when we have a typed value. from is a typed alias of fromUnknown.	Type.from	packages/common/src/Type.ts:107
fromParent	readonly	(value) => Result<InferType<T>, InferError<T>>	Creates T from Parent type. This function skips parent Types validations/transformations when we have already partially validated/transformed value. For example, TrimString.from checks whether a value is a string and trims it. If we only want to trim a string, we can use fromParent. ### Example // string & Brand<"Trimmed"> const value = TrimString.fromParent("a ").value; // as efficient as foo.trim()	Type.fromParent	packages/common/src/Type.ts:141
fromUnknown	readonly	(value) => Result<InferType<T>, | InferError<T> | InferParentError<T>>	Creates T from an unknown value. This is useful when a value is unknown.	Type.fromUnknown	packages/common/src/Type.ts:114
Input	public	InferInput<T>	The type expected by from and fromUnknown. ### Example type StringInput = typeof String.Input;	Type.Input	packages/common/src/Type.ts:90
is	readonly	(value) => value is InferType<T>	A type guard that checks whether an unknown value satisfies the Type. ### Example const value: unknown = "hello"; if (String.is(value)) { // TypeScript now knows valueis astring here. console.log("This is a valid string!"); } const strings: unknown[] = [1, "hello", true, "world"]; const filteredStrings = strings.filter(String.is); console.log(filteredStrings); // ["hello", "world"]	Type.is	packages/common/src/Type.ts:165
name	readonly	"Optional"	-	Type.name	packages/common/src/Type.ts:98
parent	readonly	T	-	-	packages/common/src/Type.ts:3621
Parent	public	InferParent<T>	The parent type. ### Example type StringParent = typeof String.Parent;	Type.Parent	packages/common/src/Type.ts:94
ParentError	public	InferParentError<T>	The parent's error. ### Example type StringParentError = typeof String.ParentError;	Type.ParentError	packages/common/src/Type.ts:96
to	readonly	(value) => InferInput	The opposite of from and fromUnknown. This is useful to transform T back to its Input representation. For refine, it only removes the brand. For transform, it changes value.	Type.to	packages/common/src/Type.ts:123
toParent	readonly	(value) => InferParent	The opposite of fromParent.	Type.toParent	packages/common/src/Type.ts:144
Type	readonly	InferType	The type this Type resolves to. ### Example type String = typeof String.Type;	Type.Type	packages/common/src/Type.ts:178