No Press Diplomacy

Syntax

This section describes the syntax of the various types of orders on the PBEM judges as well as discusses what the judge does and does not check for regarding the validity of these orders. It should be noted that in this section, validity is considered only in the context of what orders the judge will accept or reject. In many cases, the judge will accept orders which are not legal according to the Hasbro Diplomacy rules, although the adjudication or resolution of orders does follow the rules. As long as the judge accepts an order, it will appear in the move results and can be used for communication. As to whether or not the judge should accept illegal orders, that's a different matter altogether - one that I will come back to in the commentary at the end of this article.

The syntax section is divided into the following sections:
Unit Movement Orders
Fleet Convoy Orders
Support Orders
Proxy Orders
Other Orders

Unit Movement Orders

There are two different types of movement orders. The first is a "standard" move, which allows a unit to move from one space to an adjacent space. The second type of move is a convoy move which allows an army to move from one coastal province to another via fleet convoys. On the PBEM judges, the syntax for the standard move is:

<type> <s-prov> <moves> <d-prov>

and the syntax for an army being convoyed is:

<type> <s-prov> <moves> <c-prov> <moves> <c-prov> ... <moves> <d-prov>

where

<type> = "a", "army", "f", "fleet", or <empty>,
<moves> = "-", "->", "m", "move", "moves", "move to", "moves to",
<s-prov> = source province,
<d-prov> = destination province,
<c-prov> = intermediate water province in a convoy route.

For all moves (including those discussed in subsequent sections) the judge always checks that there is a unit present in the source province; any move involving a source province that does not contain a unit is automatically rejected.

For regular moves, as stated in the rules, an army may not move into a body of water, a fleet may not move to an inland province, and a destination province must always be adjacent to the source province for a move to be valid. The judge checks for all of these things and rejects invalid moves. Switzerland is considered to be impassable, so the judge rejects moves into Switzerland, even from adjacent provinces.

For army moves via convoy, the judge checks to make sure that the unit type is an army, that both the source province and the destination province are coastal provinces, that all the intermediate convoy provinces are bodies of water and that the intermediate convoy provinces contain fleets. Any army convoy move not satisfying all these criteria is rejected.

Fleet Convoy Orders

Fleet convoy orders allow one or more fleets to convoy armies from one coastal province to another. On the PBEM judges, the syntax for a fleet convoy order is:

<type> <s-prov> <convoy> <type> <s-prov> <moves> <d-prov>

where

<convoy> = "c", "convoy", "convoys".

Since only fleets can submit convoy orders and only armies can be convoyed, the judge checks to make sure that the first unit type in a convoy order is a fleet, that the second type is an army, and that the destination province for the army is not a body of water. Any orders where this is not true are rejected.

However, the judge does not check to ensure that the convoying fleet is in a body of water, nor does it check that the source and destination provinces for the army are coastal provinces, nor does it check that the bodies of water between the army's source and destination provinces contain fleets (note: in contrast, as described in the previous section, the judge does check for the presence of fleets along a convoy path for the army move via convoy order), nor does it check to see if a destination province is Switzerland. This means that a fleet in a coastal land province can submit a convoy order, that a fleet can order a convoy for an army in any province to any other land province (including Switzerland) regardless of whether a source and/or destination province is coastal or not, and irrespective of the presence of fleets along a possible convoy path.

Support Orders

The two types of support orders are to support a unit in its current position, or to support an attack. The syntax for these two support orders on the PBEM judges is:

<type> <s-prov> <support> <type> <s-prov>
<type> <s-prov> <support> <type> <s-prov> <moves> <d-prov>

where

<support> = "s", "support", "supports".

According to the rules of Diplomacy, you can only give support into a space that you could move into. The judge checks to see if a support order is feasible in this respect, and rejects orders that are not. Consequently, in the first type of order above, the two source provinces must be adjacent and in the second case the first source province (your unit's position) must be adjacent to the destination province of the unit you are supporting (though not necessarily adjacent to its source province). Since armies cannot move into water bodies and fleets can not move to inland provinces, armies cannot support moves into water and fleets cannot support moves to inland provinces. Because Switzerland is impassable, an army can not support an attack into Switzerland. These moves will also be rejected by the judge.

Proxy Orders

While there are few no-press games where proxy orders are permitted, they're included here because there is the occasional game that does allow them. On the PBEM judges, the syntax of the proxy order is:

<type> <s-prov> <proxy> <power>

where

<proxy> = "p", "proxy", "proxy to",
<power> = the first two or more characters of a power name (for some reason, the judge does not accept the one character abbreviations that it accepts for press).

When proxy is enabled, you can submit an order to proxy control of any unit - even units that do not belong to you - to another power. You can also submit an order for any unit belonging to any power, though for you to actually take control of that unit it must have been proxied to you by its owner and not another power. When you proxy control of a unit to another power, this is shown in the judge's confirmation of your moves. When you submit orders for units that are not yours, that also shows up in the move confirmation message.

Once the moves process, all orders that proxy control of one unit to another power show up in the judge's move results regardless of whether or not that power actually used the proxy by ordering the unit, and regardless of whether or not the order was submitted by the owner of the unit. However, orders that you submit for units of other powers only show up in the move results if moves for those units were proxied to you by the other power. Orders you submit for units that were not proxied to you do not appear in the move results.

One final bit of information: when a unit which is proxied to a power is not ordered by that power and the judge processes the moves, the result for that unit is "No order processed". It should be noted that the judge's interpretation of a unit marked "No order processed" is not actually no order at all, but a hold order. Thus, you can support a unit that you are proxying to somebody and if they don't order the unit, the unit will hold and receive support despite the fact that no order was submitted for the unit.

Other Orders

On the PBEM judges, the syntax of the hold order is:

<type> <s-prov> <holds>

where

<holds> = "h", "hold", "holds", "stand", "stands".

The syntax of a retreat order is one of:

<type> <s-prov> <moves> <d-prov>
<type> <s-prov> <disband>

where

<disband> = "d", "disband".

The syntax of adjustment orders is one of:

<build> <type> <s-prov>
<remove> <type> <s-prov>
<waive>

where

<build> = "b", "build" or <empty>,
<remove> = "r", "remove", "d", "disband" or <empty>,
<waive> = "w", "waive".

Given the simplicity of these orders, there's not much room for flexibility. The limitations of using these orders should be rather obvious: you can't retreat or disband a unit during a retreat phase unless it has been dislodged, you can't build or waive a build during an adjustment phase unless you have more supply centers than units, you can't build a unit unless you have a free home supply center (though in a chaos game any supply center you own counts as a home supply center for this rule), you can't build fleets in inland provinces, etc. Any orders that are not valid will be rejected by the judge.


Go back to:
Introduction

Go on to:
Communication
Commentary


Simon Szykman
(simon@diplom.org)

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