diff --git a/src/kill/kill.rs b/src/kill/kill.rs
index 483681e7a..3d73f9093 100644
--- a/src/kill/kill.rs
+++ b/src/kill/kill.rs
@@ -74,7 +74,7 @@ fn handle_obsolete(mut args: Vec<String>) -> (Vec<String>, Option<String>) {
     while i < args.len() {
         // this is safe because slice is valid when it is referenced
         let slice = &args[i].clone();
-        if slice.chars().next().unwrap() == '-' && slice.len() > 1
+        if slice.starts_with('-') && slice.len() > 1
             && slice.chars().nth(1).unwrap().is_digit(10)
         {
             let val = &slice[1..];
diff --git a/src/seq/seq.rs b/src/seq/seq.rs
index 4aa60aa64..9c07bc5ec 100644
--- a/src/seq/seq.rs
+++ b/src/seq/seq.rs
@@ -72,7 +72,7 @@ fn parse_options(args: Vec<String>, options: &mut SeqOptions) -> Result<Vec<Stri
                     break;
                 }
                 _ => {
-                    if arg.len() > 1 && arg.chars().next().unwrap() == '-' {
+                    if arg.len() > 1 && arg.starts_with('-') {
                         let argptr: *const String = &arg; // escape from the borrow checker
                         let mut chiter = unsafe { &(*argptr)[..] }.chars().skip(1);
                         let mut ch = ' ';