WIP: switch to announcement, remove extract input mess

examples/04_parallel_computation.rs

@@ -52,7 +52,7 @@
 //! This proves dagx runs tasks on multiple CPU cores simultaneously.
 //! ```
 
-use dagx::{task, DagResult, DagRunner, Task};
+use dagx::{task, DagResult, DagRunner};
 use std::time::{Duration, Instant};
 use tokio::time::sleep;
 
@@ -144,22 +144,32 @@ async fn main() -> DagResult<()> {
     };
 
     // ============================================================================
-    // SEQUENTIAL EXECUTION: Run the same 4 tasks one after another
+    // SEQUENTIAL EXECUTION: Run tasks one at a time in separate DAG executions
     // ============================================================================
     println!("Running SEQUENTIAL computation (same work, one at a time)...");
     let (sequential_time, sequential_result) = {
         let start = Instant::now();
 
-        // Run tasks sequentially (not using DAG, just raw execution)
-        let task1 = ComputeSum::new(1, 251, WORK_DELAY);
-        let task2 = ComputeSum::new(251, 501, WORK_DELAY);
-        let task3 = ComputeSum::new(501, 751, WORK_DELAY);
-        let task4 = ComputeSum::new(751, 1001, WORK_DELAY);
+        // Run each task separately to force sequential execution
+        let dag1 = DagRunner::new();
+        let sum1_handle = dag1.add_task(ComputeSum::new(1, 251, WORK_DELAY));
+        dag1.run(|fut| { tokio::spawn(fut); }).await?;
+        let r1 = dag1.get(sum1_handle)?;
 
-        let r1 = task1.run(()).await;
-        let r2 = task2.run(()).await;
-        let r3 = task3.run(()).await;
-        let r4 = task4.run(()).await;
+        let dag2 = DagRunner::new();
+        let sum2_handle = dag2.add_task(ComputeSum::new(251, 501, WORK_DELAY));
+        dag2.run(|fut| { tokio::spawn(fut); }).await?;
+        let r2 = dag2.get(sum2_handle)?;
+
+        let dag3 = DagRunner::new();
+        let sum3_handle = dag3.add_task(ComputeSum::new(501, 751, WORK_DELAY));
+        dag3.run(|fut| { tokio::spawn(fut); }).await?;
+        let r3 = dag3.get(sum3_handle)?;
+
+        let dag4 = DagRunner::new();
+        let sum4_handle = dag4.add_task(ComputeSum::new(751, 1001, WORK_DELAY));
+        dag4.run(|fut| { tokio::spawn(fut); }).await?;
+        let r4 = dag4.get(sum4_handle)?;
 
         let result = r1 + r2 + r3 + r4;
         let elapsed = start.elapsed();