Debug: TypeScript 'Type instantiation is excessively deep'

TypeScript compiler error TS2589: Type instantiation is excessively deep and possibly infinite.

This happens with deeply recursive types. Fixes:

1. Add recursion depth limit:

// BAD: Unbounded recursion
type DeepPartial<T> = { [K in keyof T]?: DeepPartial<T[K]> };

// GOOD: Add depth counter
type DeepPartial<T, Depth extends any[] = []> =
Depth['length'] extends 10 ? T :
{ [K in keyof T]?: DeepPartial<T[K], [...Depth, any]> };

1. Simplify generic chains:

// If you have Type1<Type2<Type3<Type4<T>>>>, flatten the nesting

1. Use type assertions as escape hatch:

const result = complexOperation() as ExpectedType;

1. Check for circular type references:

type A = { b: B };
type B = { a: A }; // Mutual recursion can trigger this

1. Update TypeScript — newer versions have higher limits and better detection.