Add type utilities: KeyOf, Template, DeepPartial, Partial, Required, Pick, Omit

[AliiiBenn]

Summary

Add comprehensive type utilities for type manipulation:

• KeyOf[T]: Returns all member names as a tuple of Literal types
• Template[*Parts]: Template literal string builder
• DeepPartial[T]: Make all fields recursively optional
• Partial[T]: Make all fields optional (non-recursive)
• Required[T]: Remove Optional from all fields
• Pick[T, K]: Pick specific fields from a type
• Omit[T, K]: Omit specific fields from a type

Examples

KeyOf[T]

class User:
    name: str
    age: int

# Returns tuple[Literal["name"], Literal["age"]]
type Keys = KeyOf[User]

Template[*Parts]

Resource = Literal["users"]
# Returns Literal["api/v1/users"]
type Route = Template["api/v1/", Resource]

DeepPartial[T]

class User:
    name: str
    address: Address

# All fields become optional recursively
type PartialUser = DeepPartial[User]
# Result: address.street: str | None (nested optional)

Partial[T]

class User:
    name: str
    age: int

# All fields become optional (non-recursive)
type PartialUser = Partial[User]
# Result: name: str | None, age: int | None

Required[T]

class User:
    name: str | None
    age: int | None

# Remove Optional from all fields
type RequiredUser = Required[User]
# Result: name: str, age: int

Pick[T, K]

class User:
    name: str
    email: str
    password: str

# Pick specific fields
type PublicUser = Pick[User, tuple["name", "email"]]
# Result: name: str, email: str (password excluded)

Omit[T, K]

class User:
    name: str
    email: str
    password: str

# Omit specific fields
type SafeUser = Omit[User, tuple["password"]]
# Result: name: str, email: str (password excluded)

Test Plan

• KeyOf tests (6 tests)
• Template tests (5 tests)
• DeepPartial tests (6 tests)
• Partial tests (6 tests)
• Required tests (6 tests)
• Pick tests (6 tests)
• Omit tests (7 tests)

All 155 tests pass.

🤖 Generated with Claude Code