feat: on fmt if label and name are the same only print one

crates/aiken-lang/src/format.rs

@@ -1585,7 +1585,11 @@ impl<'a> Documentable<'a> for &'a ArgName {
             ArgName::Named { name, .. } | ArgName::Discard { name, .. } => name.to_doc(),
             ArgName::LabeledDiscard { label, name, .. }
             | ArgName::NamedLabeled { label, name, .. } => {
-                docvec![label, " ", name]
+                if label == name {
+                    name.to_doc()
+                } else {
+                    docvec![label, " ", name]
+                }
             }
         }
     }

examples/sample/validators/swap.ak

@@ -3,21 +3,22 @@ use aiken/string
 use aiken/hash.{Blake2b_224, Hash}
 use aiken/transaction.{ScriptContext}
 use aiken/transaction/credential.{VerificationKey}
- 
+
 pub type Datum {
   owner: Hash<Blake2b_224, VerificationKey>,
 }
- 
+
 pub type Redeemer {
   msg: ByteArray,
 }
- 
+
 pub fn spend(datum: Datum, redeemer: Redeemer, context: ScriptContext) -> Bool {
   let must_say_hello = string.from_bytearray(redeemer.msg) == "Hello, World!"
+
   let must_be_signed =
     context.transaction.extra_signatories
     |> list.any(fn(vk) { vk == datum.owner })
- 
+
   must_say_hello && must_be_signed
 }