Adding type safety to object IDs in TypeScript
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Adding type safety to object IDs in TypeScript
1–10 of 61 posts
Re: Adding type safety to object IDs in TypeScript
#2Stripe does this (prefix ids with object type). Its smart. Makes it much easier to work with the ids.
Re: Adding type safety to object IDs in TypeScript
#3I wonder if a similar (but maybe more bloated) implementation using interfaces (and probably generics too?) will work in this case.
Re: Adding type safety to object IDs in TypeScript
#4I love this approach but I augment it with Zod branded types. IDs have a known start to their identifier and anything coming in and out of the database is verified match a schema
Re: Adding type safety to object IDs in TypeScript
#5This is pretty close to type branding (newtype wrapping for the Haskell-inclined), though using template literal types is pretty novel. Normal brands look something like this:
type Brand = BaseType & { readonly __brand__: Brand };
type FooId = Brand;
function fooBar(asdf: FooId | 'foobar'): void { }
Re: Adding type safety to object IDs in TypeScript
#6Nice!
Re: Adding type safety to object IDs in TypeScript
#7This is pretty close to type branding (newtype wrapping for the Haskell-inclined), though using template literal types is pretty novel. Normal brands look something like this: type Brand = BaseType & { readonly __brand__: Brand }; type FooId = Brand ; function fooBar(asdf: FooId | 'foobar'): void { } fooBar will only accept the literal string 'foobar' or a true FooId, but not any arbitrary string. FooId would then co…
I prefer the Brand solution, it works well for existing ID sets that you can't easily migrate to have an actual string prefix
Re: Adding type safety to object IDs in TypeScript
#8This is pretty close to type branding (newtype wrapping for the Haskell-inclined), though using template literal types is pretty novel. Normal brands look something like this: type Brand = BaseType & { readonly __brand__: Brand }; type FooId = Brand ; function fooBar(asdf: FooId | 'foobar'): void { } fooBar will only accept the literal string 'foobar' or a true FooId, but not any arbitrary string. FooId would then co…
The meaning is different though. Brands convey intent, UserId brand would allow only other UserId brands, but with string literal types "any" type that matches 'user_${string}' will do
Re: Adding type safety to object IDs in TypeScript
#9This is pretty close to type branding (newtype wrapping for the Haskell-inclined), though using template literal types is pretty novel. Normal brands look something like this: type Brand = BaseType & { readonly __brand__: Brand }; type FooId = Brand ; function fooBar(asdf: FooId | 'foobar'): void { } fooBar will only accept the literal string 'foobar' or a true FooId, but not any arbitrary string. FooId would then co…
If you want to make this easier to keep private between encapsulation boundaries the additional suggestion is make sure the Brand type extends symbol:
type Brand = BaseType & { readonly __brand__: Brand };
const FooIdBrand = Symbol('FooId');
type FooId = Brand;
function fooBar(asdf: FooId | 'foobar'): void { }
Re: Adding type safety to object IDs in TypeScript
#10Reminds me of Slack IDs:
- Channel IDs always start with C
- User IDs always start with U