From: Ian Jackson <ijackson@chiark.greenend.org.uk>
Date: Mon, 18 Apr 2022 15:23:47 +0000 (+0100)
Subject: currency: Abolish min_unit
X-Git-Tag: otter-1.1.0~470
X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=commitdiff_plain;h=0b2df958d4c49fc979efa9da192f292806538079;p=otter.git

currency: Abolish min_unit

We can instead just rely on the players to Not Do That, or to tell
each other off.  It's easy to recover from, too: just move money until
the amounts are right.

This also avoids any question of what to do if people try to combine
banknotes with the same currency but different min_qty.  (GCD?)

Suggested-by: Gareth Taylor
Signed-off-by: Ian Jackson <ijackson@chiark.greenend.org.uk>
---

diff --git a/src/currency.rs b/src/currency.rs
index a26e4236..9ad96dfd 100644
--- a/src/currency.rs
+++ b/src/currency.rs
@@ -24,18 +24,14 @@ pub struct Spec {
   image: Box<dyn PieceSpec>,
   qty: Qty,
   currency: String,
-  #[serde(default="default_min_unit")] min_unit: Qty,
 }
 
-fn default_min_unit() -> Qty { 1 }
-
 #[derive(Debug,Serialize,Deserialize)]
 pub struct Banknote {
   itemname: String,
   image: Arc<dyn InertPieceTrait>,
   qty: Qty,
   currency: String,
-  min_unit: Qty,
 }
 
 #[typetag::serde(name="Currency")]
@@ -45,7 +41,7 @@ impl PieceSpec for Spec {
           -> SpecLoaded {
     gpc.rotateable = false;
 
-    let Spec { ref image, ref currency, qty, min_unit } = *self;
+    let Spec { ref image, ref currency, qty } = *self;
 
     let SpecLoadedInert { p: image, occultable:_ } =
       image.load_inert(ig, depth)?;
@@ -59,14 +55,10 @@ impl PieceSpec for Spec {
       });
     }
         
-    if (qty % min_unit) != 0 {
-      throw!(SpecError::CurrencyQtyNotMultipleOfUnit)
-    }
-
     let bnote = Banknote {
       image: image.into(),
       currency: currency.clone(),
-      itemname, qty, min_unit,
+      itemname, qty,
     };
 
     let special = PieceSpecialProperties {