use expect() not unwrap()

diff --git a/src/main.rs b/src/main.rs
index f0728234ed208212d2032e6b7aa61c45d34c0d57..0182cc640581740ef0cf62921449b5bff81d6f48 100644 (file)
--- a/src/main.rs
+++ b/src/main.rs
@@ -7,13 +7,16 @@ fn main() -> Result<(),PolarsError> {
     // expect first arg to be a file suffix = 0, 1
     let mut argsiter = args();
     let _ = argsiter.next();
-    let suffix = argsiter.next().unwrap();
+    let suffix = argsiter.next()
+       .expect("single argument required, 0 or 1");
 
     // prep output file
-    create_dir_all("out").unwrap();
+    create_dir_all("out")
+       .expect("couldn't create out dir");
     let outfilename = format!("out/output-{}.json",suffix);
     // println!("{}",outfilename);
-    let mut file = File::create(outfilename).unwrap();
+    let mut file = File::create(outfilename)
+       .expect("couldn't create output file");
 
     // set some columns to be parsed as numeric
     let mut schema_override = Schema::new();