DeepPartial

Make all fields optional, including nested types.

Quick Example

import typemap_extensions as tm
from typemap import eval_typing

class Address:
    street: str
    city: str

class User:
    name: str
    address: Address

DeepUser = eval_typing(tm.DeepPartial[User])
# Results in: name: str | None, address: Address | None
#             AND inside Address: street: str | None, city: str | None

Signature

class DeepPartial[T]:
    """Make all fields recursively optional."""

What It Does

DeepPartial makes every field optional, including nested types. It recurses into all nested classes.

Partial vs DeepPartial

class Address:
    street: str
    city: str

class User:
    name: str
    address: Address

# Partial - only top level
PartialUser = eval_typing(tm.Partial[User])
# name: str | None
# address: Address  <-- NOT optional

# DeepPartial - all levels
DeepUser = eval_typing(tm.DeepPartial[User])
# name: str | None
# address: Address | None  <-- Also optional!
#   street: str | None
#   city: str | None

Use Cases

Deep updates - Update deeply nested structures
Recursive validation - Validate any subset of a structure
Merge operations - Merge objects with partial overrides

TypeScript Comparison

// TypeScript
type DeepUser = DeepPartial<User>;

// typemap
DeepUser = eval_typing(tm.DeepPartial[User])

Warning: DeepPartial can be slow on deeply nested structures as it must traverse all levels.