refactor: better circuit default implementation

src/circuit.rs

@@ -21,7 +21,6 @@ use crate::{
 const DIGIT_SUM_CIRCUIT_SIZE_PARAMETER: u32 = 5;
 
 /// The circuit implementation for digit sum
-#[derive(Default)]
 pub struct DigitSumCircuit<F: PrimeField> {
     /// The number with which to compute the digit sum in decimal representation
     pub number: [Value<F>; NUMBER_LENGTH],
@@ -30,6 +29,12 @@ pub struct DigitSumCircuit<F: PrimeField> {
     pub k: u32,
 }
 
+impl<F: PrimeField> Default for DigitSumCircuit<F> {
+    fn default() -> Self {
+        Self::new(0).unwrap()
+    }
+}
+
 impl<F: PrimeField> DigitSumCircuit<F> {
     /// Creates a new digit sum circuit
     pub fn new(number: u64) -> StdResult<Self> {

src/commands/graph.rs

@@ -31,8 +31,7 @@ pub struct GraphCommand {
 impl GraphCommand {
     /// Main command execution
     pub fn execute(&self) -> StdResult<()> {
-        let secret_witness_number = 1;
-        let circuit = DigitSumCircuit::<Fp>::new(secret_witness_number)?;
+        let circuit = DigitSumCircuit::<Fp>::default();
 
         let graph_layout_title = "Digit Sum Circuit";
         let graph_layout_dimensions = (self.graph_width, self.graph_height);

src/commands/verify.rs

@@ -27,7 +27,7 @@ impl VerifyCommand {
         let proof = read(proof_import_path)?;
         let proof = hex::decode(proof)?;
 
-        let circuit = DigitSumCircuit::<Fp>::new(0)?;
+        let circuit = DigitSumCircuit::<Fp>::default();
         circuit.verify(&[self.statement.into()], &proof)?;
         println!(">> Proof verified!");