ts-sql

TypeScript's type system is Turing complete, so you can not only do that, but also some insane stuff like: - A SQL database implemented purely in TypeScript type system (https://github.com/codemix/ts-sql) - Chess implemented entirely in TypeScript (and Rust) type systems (https://github.com/Dragon-Hatcher/type-system-chess) - Lambda calculus in TypeScript type system (https://ayazhafiz.com/articles/21/typescript-type-system-lam...)

I don't use them directly much, but template literal generic and contidiontal types is probably the closest a mainstream language has inched towards dependent types. Some examples of TypeScript power: - SQL database in TypeScript types: https://github.com/codemix/ts-sql - Statically typed raw SQL queries: https://github.com/andywer/squid?tab=readme-ov-file#tag-func... - (Someone fill in your TS hackery for me)

There is an implementation of SQL that operates on a table shaped type, entirely at type level. For your amusement: https://github.com/codemix/ts-sql There are a bunch of more practical takes that codegen types from your database and generate types for your queries, eg: https://github.com/adelsz/pgtyped To me the second approach seems much more pragmatic because you don’t need to run a SQL parser in your typechecker interpreter on every build

SQL implemented in typescript types - https://github.com/codemix/ts-sql

> If I would level criticisms at dialyzer it would be its sometimes difficult to read warnings, it’s speed (despite being multithreaded) and the race conditions in the VS Code plugin (which is looking for extra maintainers – if I had time I would help). One of the advantages of TypeScript is that VSCode is written in TypeScript, and both VSCode and TypeScript are developed by the same company, so there's a really nice synergy there. I imagine Kotlin users feel the same way using Jetbrains products, and Swift users feel the same way about XCode. Dialyzer looks interesting, but I can't imagine giving up on the expressiveness of TypeScript. Some of the things you can do with generics, mapped types, intersection types, template literal types, conditional types, and utility types are almost mind boggling. It's difficult to reap all of the bene

If you want to see some more legs on TypeScript type-level logic, check out this SQL database as Typescript types: https://github.com/codemix/ts-sql: import { Query } from "@codemix/ts-sql"; const db = { things: [ { id: 1, name: "a", active: true }, { id: 2, name: "b", active: false }, { id: 3, name: "c", active: true }, ], } as const; type ActiveThings = Query< "SELECT id, name AS nom FROM things WHERE active = true", typeof db >; // ActiveThings is now equal to the following type: type Expected = [{ id: 1; nom: "a" }, { id: 3; nom: "c" }];

Which allows for things like this type that implements a simplified SQL query parser checked against a provided 'database' object: https://github.com/codemix/ts-sql This project was my go-to "nifty but pointless" example for TS string literal types before this article :)

author of ts-sql[0] here, this looks great (and a way more practical approach!) [0] https://github.com/codemix/ts-sql

Another example, SQL-database-in-the-typescript-typesystem here https://github.com/codemix/ts-sql This would have been much easier if I'd had ts-regexp at the time :)

I am highly interested in type programming lately, exactly the kind of thing you're doing here. Do you have any other resources that inspired you? Here are some of my favorites: https://gist.github.com/hediet/63f4844acf5ac330804801084f87a... https://github.com/codemix/ts-sql https://github.com/jamiebuilds/json-parser-in-typescript-ver... https://gist.github.com/acutmore/9d2ce837f019608f26ff54e0b1c...

Here you go! https://github.com/codemix/ts-sql import { Query } from "@codemix/ts-sql"; const db = { things: [ { id: 1, name: "a", active: true }, { id: 2, name: "b", active: false }, { id: 3, name: "c", active: true }, ], } as const; type ActiveThings = Query< "SELECT id, name AS nom FROM things WHERE active = true", typeof db >; // ActiveThings is now equal to the following type: type Expected = [{ id: 1; nom: "a" }, { id: 3; nom: "c" }];

https://github.com/codemix/ts-sql might be worth looking at, at least the parsing section.

Maybe this may help as some inspiration https://github.com/codemix/ts-sql

Someone claimed the type system of typescript is turning complete. This example shows how to derive types from string based sql statement: https://github.com/codemix/ts-sql