Chapter 4 almost code complete

Chapter04/Cargo.toml

@@ -37,3 +37,7 @@ path = "lifetimes.rs"
 [[bin]]
 name = "parameters"
 path = "parameters.rs"
+
+[[bin]]
+name = "serialize"
+path = "serialize.rs"

Chapter04/serialize.rs

@@ -0,0 +1,28 @@
+#[macro_use] extern crate serde_derive;
+extern crate serde;
+extern crate serde_json;
+
+struct Foo
+{
+   bar: Box<u64>
+}
+
+trait T {}
+
+#[derive(Serialize,Deserialize)]
+struct S1;
+impl T for S1 {}
+
+#[derive(Serialize,Deserialize)]
+struct S2;
+impl T for S2 {}
+
+#[derive(Serialize,Deserialize)]
+struct Container
+{
+   field: Box<T>
+}
+
+fn main()
+{
+}

Chapter04/src/analyze.rs

@@ -1,7 +1,8 @@
 mod physics;
 mod motor;
 
-use physics::{ElevatorSpecification, ElevatorState, MotorInput, simulate_elevator, DataRecorder, MotorController, MotorVoltage, ElevatorStateClone};
+use physics::{ElevatorSpecification, ElevatorState, MotorInput, simulate_elevator, DataRecorder, MotorController, MotorVoltage,
+              ElevatorStateClone, ElevatorSpecificationClone};
 
 #[macro_use] extern crate serde_derive;
 extern crate serde;
@@ -31,12 +32,12 @@ fn main()
    let mut start_location = 0.0;
    for line in simlog.lines() {
       let l = line.unwrap();
-      match esp.clone() {
+      match esp {
          None => {
-            let spec: ElevatorSpecification = serde_json::from_str(&l).unwrap();
-            esp = Some(spec);
+            let spec: (u64,f64,f64,u64) = serde_json::from_str(&l).unwrap();
+            esp = Some(ElevatorSpecification::load(spec));
          },
-         Some(esp) => {
+         Some(ref esp) => {
             let (est, dst): ((f64,f64,f64,f64,f64),u64) = serde_json::from_str(&l).unwrap();
             let est = ElevatorState::load(est);
             let dl = dst_timing.len();

Chapter04/src/lib.rs

@@ -1,7 +1,8 @@
 mod physics;
 mod motor;
 
-use physics::{ElevatorSpecification, ElevatorState, MotorInput, SimpleMotorInput, simulate_elevator, DataRecorder, MotorController, MotorVoltage, ElevatorStateClone};
+use physics::{ElevatorSpecification, ElevatorState, MotorInput, SimpleMotorInput, simulate_elevator, DataRecorder, MotorController, MotorVoltage,
+              ElevatorStateClone, ElevatorSpecificationClone, Motor, SimpleMotor};
 use motor::{SmoothMotorController, SimpleMotorController};
 
 #[macro_use] extern crate serde_derive;
@@ -67,7 +68,7 @@ impl<'a, W: Write> DataRecorder for SimpleDataRecorder<'a, W>
    fn init(&mut self, esp: ElevatorSpecification, est: ElevatorState)
    {
       self.esp = esp.clone();
-      self.log.write_all(serde_json::to_string(&esp.clone()).unwrap().as_bytes()).expect("write spec to log");
+      self.log.write_all(serde_json::to_string(&esp.clone().dump()).unwrap().as_bytes()).expect("write spec to log");
       self.log.write_all(b"\r\n").expect("write spec to log");
    }
    fn poll(&mut self, est: ElevatorState, dst: u64)
@@ -152,7 +153,8 @@ pub fn run_simulation()
    let mut esp = ElevatorSpecification {
       floor_count: 0,
       floor_height: 0.0,
-      carriage_weight: 120000.0
+      carriage_weight: 120000.0,
+      motor: Box::new(SimpleMotor)
    };
    let mut floor_requests = Vec::new();
 

Chapter04/src/motor.rs

@@ -64,7 +64,7 @@ impl MotorController for SimpleMotorController
 
       let gravity_adjusted_acceleration = target_acceleration + 9.8;
       let target_force = gravity_adjusted_acceleration * self.esp.carriage_weight;
-      let target_voltage = target_force / 8.0;
+      let target_voltage = self.esp.motor.voltage_of_force(target_force);
       if target_voltage > 0.0 {
          Box::new(SimpleMotorInput::Up { voltage: target_voltage })
       } else {
@@ -160,7 +160,7 @@ impl MotorController for SmoothMotorController
 
       let gravity_adjusted_acceleration = target_acceleration + 9.8;
       let target_force = gravity_adjusted_acceleration * self.esp.carriage_weight;
-      let target_voltage = target_force / 8.0;
+      let target_voltage = self.esp.motor.voltage_of_force(target_force);
       if !target_voltage.is_finite() {
          //divide by zero etc.
          //may happen if time delta underflows

Chapter04/src/physics.rs

@@ -4,6 +4,25 @@ use floating_duration::{TimeAsFloat, TimeFormat};
 use std::{thread, time};
 use serde;
 
+pub trait Motor
+{
+   fn force_of_voltage(&self, v: f64) -> f64;
+   fn voltage_of_force(&self, v: f64) -> f64;
+}
+
+pub struct SimpleMotor;
+impl Motor for SimpleMotor
+{
+   fn force_of_voltage(&self, v: f64) -> f64
+   {
+      8.0 * v
+   }
+   fn voltage_of_force(&self, v: f64) -> f64
+   {
+      v / 8.0
+   }
+}
+
 #[derive(Clone,Serialize,Deserialize,Debug)]
 pub enum SimpleMotorInput
 {
@@ -16,12 +35,48 @@ pub trait MotorInput: MotorForce + MotorVoltage
 }
 impl MotorInput for SimpleMotorInput {}
 
-#[derive(Clone,Serialize,Deserialize,Debug)]
 pub struct ElevatorSpecification
 {
    pub floor_count: u64,
    pub floor_height: f64,
-   pub carriage_weight: f64
+   pub carriage_weight: f64,
+   pub motor: Box<Motor>
+}
+pub trait ElevatorSpecificationClone
+{
+   fn clone(&self) -> ElevatorSpecification;
+   fn dump(&self) -> (u64,f64,f64,u64);
+   fn load((u64,f64,f64,u64)) -> ElevatorSpecification;
+}
+impl ElevatorSpecificationClone for ElevatorSpecification
+{
+   fn clone(&self) -> ElevatorSpecification
+   {
+      ElevatorSpecification
+      {
+         floor_count: self.floor_count,
+         floor_height: self.floor_height,
+         carriage_weight: self.carriage_weight,
+         motor: Box::new(SimpleMotor)
+      }
+   }
+   fn dump(&self) -> (u64,f64,f64,u64)
+   {
+      (self.floor_count,
+       self.floor_height,
+       self.carriage_weight,
+       0)
+   }
+   fn load(esp: (u64,f64,f64,u64)) -> ElevatorSpecification
+   {
+      ElevatorSpecification
+      {
+         floor_count: esp.0,
+         floor_height: esp.1,
+         carriage_weight: esp.2,
+         motor: Box::new(SimpleMotor)
+      }
+   }
 }
 
 pub struct ElevatorState