Extract common logic in examples

examples/canny.rs

@@ -1,38 +1,11 @@
+mod common;
+
 use ccvl::filter;
-use ccvl::image::*;
+use ccvl::image;
 
 fn main() -> std::process::ExitCode {
-    let args = std::env::args().collect::<Vec<String>>();
-    if args.len() != 3 {
-        println!("Usage: {} IN OUT", args[0].as_str());
-        return std::process::ExitCode::FAILURE;
-    }
-
-    let input_path = args[1].as_str();
-    let output_path = args[2].as_str();
-
-    match Image::load::<Farbfeld>(input_path) {
-        Err(Error::Invalid) => {
-            println!("{} is not a valid image", input_path);
-            std::process::ExitCode::FAILURE
-        }
-        Err(Error::Io(err)) => {
-            println!("I/O error loading image {}: {}", input_path, err);
-            std::process::ExitCode::FAILURE
-        }
-        Ok(img) => {
-            let result = filter::canny(img.map(|p| Luminance::from(p)))
-                .map(|p| p.into());
-            match result.save::<Farbfeld>(output_path) {
-                Err(err) => {
-                    println!(
-                        "I/O error saving image {}: {}",
-                        output_path, err
-                    );
-                    std::process::ExitCode::FAILURE
-                }
-                Ok(()) => std::process::ExitCode::SUCCESS,
-            }
-        }
-    }
+	common::process_image(|img| {
+		let greyscale = img.map(|p| image::Luminance::from(p));
+		filter::canny(greyscale).map(|p| p.into())
+	})
 }

examples/common/mod.rs

@@ -0,0 +1,33 @@
+use ccvl::image::*;
+
+pub fn process_image<F>(f: F) -> std::process::ExitCode
+where
+    F: FnOnce(Image<SRGBA>) -> Image<SRGBA>,
+{
+    let args = std::env::args().collect::<Vec<String>>();
+    if args.len() != 3 {
+        println!("Usage: {} IN OUT", args[0].as_str());
+        return std::process::ExitCode::FAILURE;
+    }
+
+    let input_path = args[1].as_str();
+    let output_path = args[2].as_str();
+
+    match Image::load::<Farbfeld>(input_path) {
+        Err(Error::Invalid) => {
+            println!("{} is not a valid image", input_path);
+            std::process::ExitCode::FAILURE
+        }
+        Err(Error::Io(err)) => {
+            println!("I/O error loading image {}: {}", input_path, err);
+            std::process::ExitCode::FAILURE
+        }
+        Ok(img) => match f(img).save::<Farbfeld>(output_path) {
+            Err(err) => {
+                println!("I/O error saving image {}: {}", output_path, err);
+                std::process::ExitCode::FAILURE
+            }
+            Ok(()) => std::process::ExitCode::SUCCESS,
+        },
+    }
+}

examples/greyscale.rs

@@ -1,34 +1,9 @@
-use ccvl::image::*;
+mod common;
 
-fn filter(img: Image<SRGBA>) -> Image<SRGBA> {
-    img.map(|p| Luminance::from(p).into())
-}
+use ccvl::image;
 
 fn main() -> std::process::ExitCode {
-    let args = std::env::args().collect::<Vec<String>>();
-    if args.len() != 3 {
-        println!("Usage: {} IN OUT", args[0].as_str());
-        return std::process::ExitCode::FAILURE;
-    }
-
-    let input_path = args[1].as_str();
-    let output_path = args[2].as_str();
-
-    match Image::load::<Farbfeld>(input_path) {
-        Err(Error::Invalid) => {
-            println!("{} is not a valid image", input_path);
-            std::process::ExitCode::FAILURE
-        }
-        Err(Error::Io(err)) => {
-            println!("I/O error loading image {}: {}", input_path, err);
-            std::process::ExitCode::FAILURE
-        }
-        Ok(img) => match filter(img).save::<Farbfeld>(output_path) {
-            Err(err) => {
-                println!("I/O error saving image {}: {}", output_path, err);
-                std::process::ExitCode::FAILURE
-            }
-            Ok(()) => std::process::ExitCode::SUCCESS,
-        },
-    }
+	common::process_image(|img| {
+		img.map(|p| image::Luminance::from(p).into())
+	})
 }