Add non-functional page dimension options to dyesub-cli, implement Error in svg-units

svg-units/src/lib.rs

@@ -2,7 +2,7 @@ mod unit;
 pub use unit::SVGUnit;
 
 mod measure;
-pub use measure::SVGMeasure;
+pub use measure::{SVGMeasure, SVGMeasureParseError};
 
 #[cfg(test)]
 mod tests;

svg-units/src/measure.rs

@@ -1,5 +1,5 @@
 use super::SVGUnit;
-use derive_more::From;
+use err_derive::Error;
 use lazy_static::lazy_static;
 use regex::Regex;
 use std::cmp::Ordering;
@@ -35,15 +35,18 @@ impl SVGMeasure {
     }
 }
 
-#[derive(From, Debug)]
-pub enum SVGUnitParseError {
-    ParseMeasure(ParseFloatError),
-    ParseUnit(ParseError),
+#[derive(Debug, Error)]
+pub enum SVGMeasureParseError {
+    #[error(display = "Failed to parse measure number")]
+    ParseMeasure(#[source] ParseFloatError),
+    #[error(display = "Failed to parse measure unit")]
+    ParseUnit(#[source] ParseError),
+    #[error(display = "Invalid measure format")]
     Invalid,
 }
 
 impl FromStr for SVGMeasure {
-    type Err = SVGUnitParseError;
+    type Err = SVGMeasureParseError;
     fn from_str(s: &str) -> Result<Self, Self::Err> {
         if s == "0" {
             return Ok(SVGMeasure::new(0.0, SVGUnit::Pixel));
@@ -56,11 +59,19 @@ impl FromStr for SVGMeasure {
             let unit = captures[2].parse::<SVGUnit>()?;
             Ok(SVGMeasure::new(measure, unit))
         } else {
-            Err(SVGUnitParseError::Invalid)
+            Err(SVGMeasureParseError::Invalid)
         }
     }
 }
 
+impl<'s> TryFrom<&'s str> for SVGMeasure {
+    type Error = SVGMeasureParseError;
+
+    fn try_from(value: &'s str) -> Result<Self, Self::Error> {
+        Self::from_str(value)
+    }
+}
+
 const EQ_TOLERANCE: f64 = 0.00001;
 
 impl PartialEq for SVGMeasure {