Sql Command parameter extraction

SqlParams.ts

type WhiteSpace = ' ' | '\t' | '\n' | '\r' | '\f'

type Trim<S extends string> =
    S extends `${WhiteSpace}${infer T}` ? Trim<T>
    : S extends `${infer T}${WhiteSpace}` ? Trim<T>
    : S

type SqlParamsUnion<T extends string, P extends string = '@'> =
    T extends `${any}${P}${infer P}${WhiteSpace}${infer R}`
    ? Trim<P> | SqlParamsUnion<R>
    : never;

type DbType = string | number | boolean | Date | null;

export type ParamType<T extends DbType = DbType> = T | { dbType: any, value: T }

export type SqlParamsObject<T extends string, P extends string = '@'> = {
    [K in SqlParamsUnion<T, P>]: ParamType
};

usage.ts

import { SqlParamsObject } from './SqlParams.ts';

// this will enforce that each sql param for the command is passed in if listed in the command
// and if the type of the sql string is known at the callsite)
export const execSql = async <T extends string>(sql: T, params: SqlParamsObject<T>) => {
  //...do stuff
}
  

const sql = `
select
    *
from bbb
where bbb.id = @id
    and type = @hello
`;
  
// This passes type checking:
execSql(sql, {
  hello: 'world',
  id: 10,
});
  
// These do not
execSql(sql, {
  hello: 'world',
}); // Property 'id' is missing in type '{ hello: string; }'

execSql(sql, {
  hello: 'world',
  id: 10
  something: 'else',
}); // Object literal may only specify known properties, and 'something' does not exist in type