fix: Conversion goals and value printing

pantograph/expr.py

@@ -28,7 +28,7 @@ class Variable:
         result = self.name if self.name else "_"
         result += f" : {self.t}"
         if self.v:
-            result += f" = {self.v}"
+            result += f" := {self.v}"
         return result
 
 @dataclass(frozen=True)
@@ -36,6 +36,7 @@ class Goal:
     variables: list[Variable]
     target: Expr
     name: Optional[str] = None
+    is_conversion: bool = False
 
     @staticmethod
     def sentence(target: Expr) -> Self:
@@ -46,11 +47,13 @@ class Goal:
         name = payload.get("userName")
         variables = [Variable._parse(v) for v in payload["vars"]]
         target = parse_expr(payload["target"])
-        return Goal(variables, target, name)
+        is_conversion = payload["isConversion"]
+        return Goal(variables, target, name, is_conversion)
 
     def __str__(self):
+        front = "|" if self.is_conversion else "⊢"
         return "\n".join(str(v) for v in self.variables) + \
-            f"\n⊢ {self.target}"
+            f"\n{front} {self.target}"
 
 @dataclass(frozen=True)
 class GoalState: