Some simple Option / Result / iterator pattern simplifications (#3205)

api/src/handlers/chain_api.rs

@@ -463,10 +463,7 @@ impl KernelHandler {
 				height,
 				mmr_index,
 			});
-		match kernel {
-			Some(kernel) => Ok(kernel),
-			None => Err(ErrorKind::NotFound.into()),
-		}
+		kernel.ok_or_else(|| ErrorKind::NotFound.into())
 	}
 }
 

api/src/types.rs

@@ -334,10 +334,10 @@ impl OutputPrintable {
 	}
 
 	pub fn range_proof(&self) -> Result<pedersen::RangeProof, ser::Error> {
-		let proof_str = match self.proof.clone() {
-			Some(p) => p,
-			None => return Err(ser::Error::HexError(format!("output range_proof missing"))),
-		};
+		let proof_str = self
+			.proof
+			.clone()
+			.ok_or_else(|| ser::Error::HexError(format!("output range_proof missing")))?;
 
 		let p_vec = util::from_hex(proof_str)
 			.map_err(|_| ser::Error::HexError(format!("invalid output range_proof")))?;

api/src/web.rs

@@ -105,10 +105,7 @@ impl QueryParams {
 	}
 
 	pub fn get(&self, name: &str) -> Option<&String> {
-		match self.params.get(name) {
-			None => None,
-			Some(v) => v.first(),
-		}
+		self.params.get(name).and_then(|v| v.first())
 	}
 }