Change erorr handling

rclrust/src/error.rs

@@ -135,10 +135,10 @@ pub enum RclRustError {
 
     #[error("Runtime Error: {0}")]
     RuntimeError(&'static str),
-    #[error("Service is canceled.")]
-    ServiceIsCanceled,
     #[error("Internal message queue if full: {type_} {name}")]
     MessageQueueIsFull { type_: &'static str, name: String },
+    #[error("Out of range: {0}")]
+    OutOfRange(String),
 
     // Parameter
     #[error(r#"Parameter "{name}" cannot be set because it was not declared."#)]

rclrust/src/parameter/type_.rs

@@ -1,4 +1,9 @@
+use std::convert::TryFrom;
+
+use anyhow::Result;
+
 use super::RclParameterType;
+use crate::error::RclRustError;
 
 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
 pub enum ParameterType {
@@ -14,9 +19,11 @@ pub enum ParameterType {
     StringArray,
 }
 
-impl From<u8> for ParameterType {
-    fn from(v: u8) -> Self {
-        match v {
+impl TryFrom<u8> for ParameterType {
+    type Error = anyhow::Error;
+
+    fn try_from(v: u8) -> Result<Self> {
+        Ok(match v {
             RclParameterType::PARAMETER_NOT_SET => Self::NotSet,
             RclParameterType::PARAMETER_BOOL => Self::Bool,
             RclParameterType::PARAMETER_INTEGER => Self::Integer,
@@ -27,7 +34,13 @@ impl From<u8> for ParameterType {
             RclParameterType::PARAMETER_INTEGER_ARRAY => Self::IntegerArray,
             RclParameterType::PARAMETER_DOUBLE_ARRAY => Self::DoubleArray,
             RclParameterType::PARAMETER_STRING_ARRAY => Self::StringArray,
-            _ => unreachable!(),
-        }
+            _ => {
+                return Err(RclRustError::OutOfRange(format!(
+                    "{} cannot be converted into RclParameterType",
+                    v
+                ))
+                .into())
+            }
+        })
     }
 }

rclrust/src/parameter/value.rs

@@ -1,4 +1,4 @@
-use std::fmt;
+use std::{convert::TryInto, fmt};
 
 use super::{ParameterDescriptor, ParameterType, RclParameterType, RclParameterValue};
 use crate::internal::ffi::SizedFromCChar;
@@ -124,7 +124,7 @@ impl ParameterValue {
     }
 
     pub fn get_type(&self) -> ParameterType {
-        self.0.type_.into()
+        self.0.type_.try_into().unwrap()
     }
 
     pub fn get_value(&self) -> Option<Variant> {