Add an example usage in the check command

Feel free to do this differently, I just implemented it because i'm actually using it heh

crates/aiken/src/cmd/check.rs

@@ -1,5 +1,10 @@
 use std::path::PathBuf;
 
+use aiken_project::watch;
+use owo_colors::{OwoColorize, Stream::Stderr};
+
+use crate::Terminal;
+
 #[derive(clap::Args)]
 /// Type-check an Aiken project
 pub struct Args {
@@ -18,10 +23,14 @@ pub struct Args {
     #[clap(long)]
     debug: bool,
 
-    // When enabled, re-run the command on file changes instead of exiting
+    /// When enabled, re-run the command on file changes instead of exiting
     #[clap(long)]
     watch: bool,
 
+    /// When enabled, clear the screen before running
+    #[clap(long)]
+    clear: bool,
+
     /// Only run tests if they match any of these strings.
     /// You can match a module with `-m aiken/list` or `-m list`.
     /// You can match a test with `-m "aiken/list.{map}"` or `-m "aiken/option.{flatten_1}"`
@@ -47,9 +56,77 @@ pub fn exec(
         match_tests,
         exact_match,
         no_traces,
+        watch,
+        clear,
         ..
     }: Args,
 ) -> miette::Result<()> {
+    if watch {
+        watch::watch_project(directory, Terminal, watch::default_filter, 500, |p| {
+            if clear {
+                println!("{esc}c", esc = 27 as char);
+            }
+            let build_result = p.check(
+                skip_tests,
+                match_tests.clone(),
+                debug,
+                exact_match,
+                (!no_traces).into(),
+            );
+
+            let warnings = p.warnings();
+
+            let warning_count = warnings.len();
+
+            for warning in &warnings {
+                warning.report()
+            }
+
+            let plural = if warning_count == 1 { "" } else { "s" };
+
+            if let Err(errs) = build_result {
+                for err in &errs {
+                    err.report()
+                }
+
+                eprintln!(
+                    "\n{}",
+                    "Summary"
+                        .if_supports_color(Stderr, |s| s.purple())
+                        .if_supports_color(Stderr, |s| s.bold())
+                );
+
+                let warning_text = format!("{warning_count} warning{plural}");
+
+                let plural = if errs.len() == 1 { "" } else { "s" };
+
+                let error_text = format!("{} error{}", errs.len(), plural);
+
+                let full_summary = format!(
+                    "    {}, {}",
+                    error_text.if_supports_color(Stderr, |s| s.red()),
+                    warning_text.if_supports_color(Stderr, |s| s.yellow())
+                );
+
+                eprintln!("{full_summary}");
+            } else {
+                eprintln!(
+                    "\n{}",
+                    "Summary"
+                        .if_supports_color(Stderr, |s| s.purple())
+                        .if_supports_color(Stderr, |s| s.bold())
+                );
+
+                let warning_text = format!("{warning_count} warning{plural}");
+
+                eprintln!(
+                    "    0 errors, {}",
+                    warning_text.if_supports_color(Stderr, |s| s.yellow()),
+                );
+            }
+            Ok(())
+        })
+    } else {
         crate::with_project(directory, deny, |p| {
             p.check(
                 skip_tests,
@@ -59,4 +136,5 @@ pub fn exec(
                 (!no_traces).into(),
             )
         })
+    }
 }