Merge pull request #441 from ink-feather-org/feat/improve_error_handling

Make error type 'static.

Author: AaronErhardt

plotters-backend/src/lib.rs

@@ -105,7 +105,7 @@ impl<E: Error + Send + Sync> Error for DrawingErrorKind<E> {}
 ///  will use the pixel-based approach to draw other types of low-level shapes.
 pub trait DrawingBackend: Sized {
     /// The error type reported by the backend
-    type ErrorType: Error + Send + Sync;
+    type ErrorType: Error + Send + Sync + 'static;
 
     /// Get the dimension of the drawing backend in pixels
     fn get_size(&self) -> (u32, u32);

plotters/examples/console.rs

@@ -151,10 +151,7 @@ impl DrawingBackend for TextDrawingBackend {
 
 fn draw_chart<DB: DrawingBackend>(
     b: DrawingArea<DB, plotters::coord::Shift>,
-) -> Result<(), Box<dyn Error>>
-where
-    DB::ErrorType: 'static,
-{
+) -> Result<(), Box<dyn Error>> {
     let mut chart = ChartBuilder::on(&b)
         .margin(1)
         .caption("Sine and Cosine", ("sans-serif", (10).percent_height()))