Enum Types

Enum Types

PyGo provides native support for enumerated types (enum) with compile-time validation. Enums are defined in the .pgo DSL and are mechanically transpiled to idiomatic Go and Python code.

Defining an Enum

String-backed Enums (Default)

enum Status:
  active
  inactive
  pending

Numeric Enums

enum Role:
  admin=1
  author=2
  reader=3

Generated Code

Go

type Status string

const (
    StatusActive   Status = "active"
    StatusInactive Status = "inactive"
    StatusPending  Status = "pending"
)

type Role int

const (
    RoleAdmin  Role = 1
    RoleAuthor Role = 2
    RoleReader Role = 3
)

Python

import enum

class Status(str, enum.Enum):
    ACTIVE = "active"
    INACTIVE = "inactive"
    PENDING = "pending"

class Role(int, enum.Enum):
    ADMIN = 1
    AUTHOR = 2
    READER = 3

Using Enums in Models

enum Status:
  active
  inactive

model User:
  id: UUID
  name: String
  status: Status
  role: Role

Enum Validation

Enums are validated at compile time:

model Post:
  title: String
  status: Status

# Valid
post = Post(title="Hello", status=Status.published)

# Invalid — compile-time error (not a valid Status value)
# post = Post(title="Hello", status="published")

Database Representation

By default, PyGo stores enums as their string value in the database:

CREATE TABLE user (
    id UUID PRIMARY KEY,
    name TEXT NOT NULL,
    status TEXT NOT NULL,  -- stores "active", "inactive", "pending"
    role INTEGER          -- stores 1, 2, 3 (for numeric enums)
);

Best Practices

• Use string-backed enums for human-readable values
• Use numeric enums for storage efficiency when values don’t need to be human-readable
• Always use the enum constant, never raw strings