- Sashité for Developers
- Specifications
- PMN
- 1.0.0
- Examples
PMN Examples
Learn Portable Move Notation (PMN) through progressive examples, from basic moves to multi-action moves (captures, drops, special moves).
PMN encodes Moves (ordered sequences of protocol-level Actions). Many moves are 1 Action, but some PMN forms imply 2 Actions (e.g., capture-moves and capture-drops).
Quick reference
Forms (operators and shapes)
| Form | Example | Meaning | Direct effect (Actions) |
|---|---|---|---|
| Pass | ... |
Pass move | 0 |
| Move (quiet) | e2-e4 |
Move to empty square | 1 |
| Move (capture) | d1+f3 |
Capture at destination then move actor | 2 |
| Static capture | +d4 |
Capture a piece on a square (no actor move) | 1 |
| Special move | e1~g1 |
Move with rule-defined implicit effects | ≥ 1 |
| Drop (quiet) | P*e5 or *e5 |
Drop from hand to empty square | 1 |
| Drop (capture) | L.b4 or .b4 |
Capture at destination then drop actor | 2 |
| In-place mutation | e4=+P |
Mutate piece already on a square | 1 |
Notes:
+has two forms: infix (src+dst) and prefix (+square).=is both an operator (square=piece) and a suffix (...=piece) depending on context.
Suffixes (transformations)
Suffixes MAY be appended to certain forms:
| Suffix | Example | Applies to | Meaning |
|---|---|---|---|
=<piece> |
e7-e8=Q |
Actor Action | Mutate the acting piece |
/<piece> |
d4+e5/P |
Capture Action | Mutate the captured piece before it goes to a hand |
Ordering (when both exist): ...=.../... (actor first, then captured).
Basic moves
Simple move (-)
e2-e4
Meaning: the piece at e2 moves to the empty square e4.
Direct effect:
- 1 Action: Board(
e2) → Board(e4)
Capture-move (src+dst)
d1+f3
Meaning: capture the piece on f3, then move the actor from d1 to f3.
Direct effect:
- 2 Actions:
1) Board(
f3) → Hand(rule-defined) 2) Board(d1) → Board(f3)
Transformations (EPIN)
Actor transformation (=<piece>)
e7-e8=Q
Meaning: the pawn moves from e7 to e8 and mutates into a queen.
Direct effect:
- 1 Action: Board(
e7) → Board(e8) with actor mutation toQ
Capture transformation (/<piece>)
d4+e5/P
Meaning: the piece at d4 captures on e5, and the captured piece is transformed into P before being placed into a hand.
Direct effect:
- 2 Actions:
1) Board(
e5) → Hand(rule-defined) with captured mutation toP2) Board(d4) → Board(e5)
This is especially useful in shōgi-like rule systems where captured promoted pieces revert to their base form.
Combined transformations
b7+a8=Q/R
Meaning: capture on a8, mutate actor to Q, mutate captured piece to R in hand.
Direct effect:
- 2 Actions (capture first, then actor move), with both mutations applied to their respective Actions.
Static capture (+square)
Capture without moving an actor
+d4
Meaning: capture the piece located on d4 (useful for custodial captures, ranged effects, or rule-driven removals).
Direct effect:
- 1 Action: Board(
d4) → Hand(rule-defined)
With capture transformation
+d4/p
Meaning: same capture, but the captured piece is transformed to p before it goes to a hand.
Special moves (~)
Castling-like example
e1~g1
Meaning: the actor moves from e1 to g1. The ~ signals the Rule System may add implicit effects (e.g., moving a rook).
Direct effect:
- ≥ 1 Action: Board(
e1) → Board(g1)
Implicit effects (rule-defined):
- May include additional Actions (e.g., rook displacement).
En passant-like example
e5~f6/p
Meaning: the actor moves from e5 to f6, and the Rule System may apply an implicit capture (e.g., en passant). If an implicit capture occurs, /<piece> specifies how the captured piece is mutated.
Important:
- If no capture occurs under the Rule System,
/<piece>has no effect.
Drops
Drop to empty square (*)
P*e5
Meaning: drop a pawn from hand onto e5.
Direct effect:
- 1 Action: Hand(rule-defined) → Board(
e5)
Contextual drop (piece omitted)
*e5
Meaning: drop some piece from hand onto e5.
Guideline:
- Omitting the piece is only appropriate if the Rule System (or surrounding context) can uniquely determine which hand-piece is being dropped.
Drop with capture (.)
L.b4
Meaning: capture the piece on b4, then drop L onto b4.
Direct effect:
- 2 Actions:
1) Board(
b4) → Hand(rule-defined) 2) Hand(rule-defined) → Board(b4) (droppingL)
In-place mutation (square=piece)
e4=+P
Meaning: mutate the piece currently on e4 into +P without moving it.
Direct effect:
- 1 Action: mutation-only on Board(
e4)
Game sequence example
A chess opening (Italian Game), expressed as PMN moves:
e2-e4
e7-e5
g1-f3
b8-c6
f1-c4
f8-c5
Each line is one Move (typically 1 Action here), alternating between sides.