add Display impl for printing PortRegistration

src/main.rs

@@ -1,5 +1,5 @@
 use serde::Deserialize;
-use std::{env,fs::File};
+use std::{env,fmt,fs::File};
 use std::io::BufReader;
 use std::collections::{HashMap, HashSet};
 use std::path::{Path, PathBuf};
@@ -48,6 +48,17 @@ struct PortRegistration {
     service: Option<String>,
 }
 
+impl fmt::Display for PortRegistration {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        write!(f, "in {}, job \"{}\", group \"{}\", task \"{}\", service \"{}\"",
+               self.file.display(), self.job, self.group, self.task,
+               match &self.service {
+                   None => "<noname>",
+                   Some(s) => s
+               })
+    }
+}
+
 impl Ctx {
     pub fn new() -> Self {
         Ctx { ports: HashMap::new() }
@@ -138,12 +149,7 @@ fn main() -> Result<ExitCode> {
             have_conflicts = true;
             println!("Conflict in site {}, port {:?}:", &datacenter, port);
             for reg in &regs {
-                println!("- in {}, job \"{}\", group \"{}\", task \"{}\", service \"{}\"",
-                         reg.file.display(), reg.job, reg.group, reg.task,
-                         match &reg.service {
-                             None => "<noname>",
-                             Some(s) => s
-                         })
+                println!("- {}", reg)
             }
             println!()
         }