notable restructuring

examples/vcd1.rs

@@ -0,0 +1,34 @@
+use clap::Parser;
+use std::fs::File;
+
+use fastwave::*;
+
+use num::{BigUint};
+
+fn main() -> std::io::Result<()> {
+
+    use std::time::Instant;
+    
+    let now = Instant::now();
+    let file_path = "tests/vcd-files/icarus/CPU.vcd";
+    let file = File::open(file_path).unwrap();
+    let vcd = parse_vcd(file).unwrap();
+    let elapsed = now.elapsed();
+
+    println!("Parsed VCD file {} : {:.2?}", file_path, elapsed);
+
+    // testbench -> CPU -> rs2_data[31:0] @ 4687s
+    let rs2_data_signal = &vcd.all_signals[51];
+    let name = rs2_data_signal.name();
+    let time = BigUint::from(4687u32);
+    let val = rs2_data_signal
+        .query_num_val_on_tmln(
+            &time,
+            &vcd.tmstmps_encoded_as_u8s,
+            &vcd.all_signals,
+        )
+        .unwrap();
+    println!("Signal `{name}` has value `{val}` at time `{time}`");
+
+    Ok(())
+}