NominalType

NominalType<TKey, TMarker> = { readonly [K in `__${TKey}:@solana/kit`]: TMarker }

Use this to produce a nominal type.

This can be intersected with other base types to produce custom branded types.

Type Parameters

Type Parameter	Description
`TKey` extends `string`	The name of the nominal type. This distinguishes one nominal type from another.
`TMarker` extends `string`	The type of the value the nominal type can take.

Example

type SweeteningSubstance = 'aspartame' | 'cane-sugar' | 'stevia';
type Sweetener<T extends SweeteningSubstance> = NominalType<'sweetener', T>;
 
// This function accepts sweetened foods, except those with aspartame.
declare function eat(food: string & Sweetener<Exclude<SweeteningSubstance, 'aspartame'>>): void;
 
const artificiallySweetenedDessert = 'ice-cream' as string & Sweetener<'aspartame'>;
eat(artificiallySweetenedDessert); // ERROR

NominalType

Type Parameters

Example

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