Rulealize.Plugin.Deck 1.0.0

Rulealize.Plugin.Deck

Piles of cards for Rulealize rule sets.

A pile is how many of each card are in it. deck.of declares which cards exist, deck.move moves a card from one pile to another, deck.draw is the card a pile gives up, and deck.count, deck.size and deck.cards read a pile.

"state": {
  "schema": {
    "deck": { "op": "deck.of", "cards": ["A", "2", "3", "4", "5", "6", "7", "8", "9", "T"] },
    "hand": { "op": "deck.of", "cards": ["A", "2", "3", "4", "5", "6", "7", "8", "9", "T"] }
  },
  "initial": { "deck": { "A": 4, "2": 4, "3": 4 }, "hand": {} }
},

"inputs": {
  "draw":  { "effects": [ { "op": "deck.move", "from": "$deck", "to": "$hand",
                            "card": { "op": "deck.draw", "of": "$deck" } } ] },
  "play":  { "params": { "card": { "domain": { "op": "deck.cards", "of": "$hand" } } },
             "effects": [ { "op": "deck.move", "from": "$hand", "to": "$table", "card": "@card" } ] }
}

A pile is counts, not an order

What is on top of a shuffled deck is not something a rule set may know. A draw enumerates what could come out and how likely each of those is; an order written into the state would be either a secret carried in plain sight or a decision nobody made. Counts say exactly what is knowable, and deck.draw weights its candidates by them — so drawing from a deck holding four aces and one king is five outcomes with the right probabilities, and a search over the position is the same two calls as a search over a game with no cards in it.

A deck and a hand are the same kind of field

So are a discard pile and the table. What separates them is which field a card is in, which is why every operation here moves cards between two fields rather than taking and giving. A rule set with four piles declares four fields of the same shape.

Why dealing is a draw inside a move

A draw evaluated twice is two draws. "Put the drawn card in the hand" and "take the drawn card out of the deck" written as two effects would therefore move two different cards — so the draw is written where the card is wanted, as the card of the move, and is evaluated once. It is also why rule sets written before this plugin did not store a deck at all, and recomputed what was left from what had been dealt.

It does not shuffle anything

There is no random number generator in this assembly. deck.draw works out the candidates and their weights and hands them to the runtime, which says which one this evaluation is for — the same arrangement Chance has, and it needs a runtime that resolves draws for the same reason.

Building

dotnet build. Rulealize.Abstraction restores from nuget.org like any other package, so this repository builds on its own.

License

Apache-2.0.