add error msgs

core/src/runtime.rs

@@ -181,7 +181,7 @@ impl KompactConfig {
     /// Larger values can increase throughput on highly loaded components,
     /// but at the cost of fairness between components.
     pub fn throughput(&mut self, n: usize) -> &mut Self {
-        assert!(n > 0);
+        assert!(n > 0, "throughput must be larger than 0");
         self.throughput = n;
         self
     }
@@ -195,7 +195,7 @@ impl KompactConfig {
     /// the remaining allotment will be redistributed to the other type
     /// until all throughput is used up or no messages or events remain.
     pub fn msg_priority(&mut self, r: f32) -> &mut Self {
-        assert!(r > 0.0);
+        assert!(r > 0.0, "msg_priority must be larger than 0.0");
         self.msg_priority = r;
         self
     }
@@ -207,7 +207,7 @@ impl KompactConfig {
     /// You *must* ensure that the selected [scheduler](KompactConfig::scheduler) implementation
     /// can manage the given number of threads, if you customise this value!
     pub fn threads(&mut self, n: usize) -> &mut Self {
-        assert!(n > 0);
+        assert!(n > 0, "threads must be larger than 0");
         self.threads = n;
         self
     }