added arrow tips (WIP)

src/sequence.typ

@@ -2,12 +2,30 @@
 #import "consts.typ": *
 #import "participant.typ"
 
+#let get-arrow-marks(sym, color) = {
+  if type(sym) == array {
+    return sym.map(s => get-arrow-marks(s, color))
+  }
+  (
+    "": none,
+    ">": (symbol: ">", fill: color),
+    ">>": (symbol: "straight"),
+    "\\": (symbol: ">", fill: color, harpoon: true, flip: true),
+    "\\\\": (symbol: "straight", harpoon: true, flip: true),
+    "/": (symbol: ">", fill: color, harpoon: true),
+    "//": (symbol: "straight", harpoon: true),
+    "x": none,
+    "o": (symbol: "o"),
+  ).at(sym)
+}
+
 #let _seq(
   p1,
   p2,
   comment: none,
   dashed: false,
-  tip: "default",
+  start-tip: "",
+  end-tip: ">",
   color: black,
   flip: false,
   enable-dst: false,
@@ -24,7 +42,8 @@
     p2: p2,
     comment: comment,
     dashed: dashed,
-    tip: tip,
+    start-tip: start-tip,
+    end-tip: end-tip,
     color: color,
     flip: flip,
     enable-dst: enable-dst,
@@ -119,7 +138,10 @@
   }
 
   let style = (
-    mark: (end: ">", fill: elmt.color),
+    mark: (
+      start: get-arrow-marks(elmt.start-tip, elmt.color),
+      end: get-arrow-marks(elmt.end-tip, elmt.color)
+    ),
     stroke: (
       dash: if elmt.dashed {"dashed"} else {"solid"},
       paint: elmt.color