Crate rbp_gameplay 

Poker game engine with state management, action handling, and settlement.

This module implements the rules and mechanics of No-Limit Texas Hold’em, tracking game state across betting rounds and resolving showdowns.

State Representation

• Game — The memoryless present: stacks, pot, board, and active players
• Partial — The remembered past: complete action history for a hand
• Path — Compressed action sequence for tree traversal

Actions

• Action — A player decision: fold, check, call, or raise
• Edge — A game tree transition with the acting player
• Odds — Pot odds abstraction for bet sizing (1/3, 1/2, 2/3, pot, all-in)

Resolution

• Showdown — Final hand comparison when multiple players remain
• Settlement — Pot distribution with side-pot handling
• PnL — Profit and loss accounting per player

Supporting Types

• Seat — Player position and stack at the table
• Turn — Whose action it is and what options they have
• Arrangement — Positional configuration for heads-up or multiway
• Abstraction — Abstract bucket assignment for strategic equivalence

Information Levels

• Partial — Partial information: hero’s cards only (concrete)
• Perfect — Complete information: both players’ cards (concrete)

Structs

Abstraction

A discrete bucket representing strategically similar hands.

Arrangement

An ordered sequence of up to 7 cards as dealt.

Game

The memoryless state of a poker hand.

Hands

Iterator over completed hands in a session.

Odds

Pot-relative bet sizing as a fraction.

Partial

Perfect-recall game history from a single player’s perspective.

Path

A compact sequence of abstract edges packed into 64 bits.

Perfect

Complete game history with both players’ cards known.

Perpetual

Infinite iterator over actions across games.

PnL

Public profit/loss information.

Seat

A player’s state at the table.

Session

Iterator over actions in a session.

Settlement

A player’s final result including hand strength.

Showdown

Computes chip distributions at showdown.

Enums

Action

A player decision or chance event in the game.

Edge

An abstracted game tree transition.

PositionName

Named position at a poker table relative to the dealer button.

Size

Abstract bet sizing for Edge::Raise.

State

Player betting status within a hand.

Turn

Whose turn it is to act in the game tree.

Traits

Recall

A game history that can be replayed from a root state.