diff --git a/sim/simflash/src/lib.rs b/sim/simflash/src/lib.rs
index 009148c..532fb0e 100644
--- a/sim/simflash/src/lib.rs
+++ b/sim/simflash/src/lib.rs
@@ -230,7 +230,7 @@
     /// Adds a new flash bad region. Writes to this area fail with a chance
     /// given by `rate`.
     fn add_bad_region(&mut self, offset: usize, len: usize, rate: f32) -> Result<()> {
-        if rate < 0.0 || rate > 1.0 {
+        if !(0.0..=1.0).contains(&rate) {
             bail!(ebounds("Invalid rate"));
         }
 
diff --git a/sim/simflash/src/pdump.rs b/sim/simflash/src/pdump.rs
index c68aa83..6243065 100644
--- a/sim/simflash/src/pdump.rs
+++ b/sim/simflash/src/pdump.rs
@@ -34,7 +34,7 @@
             self.hex.push(' ');
         }
         self.hex.push_str(&format!(" {:02x}", ch)[..]);
-        self.ascii.push(if ch >= ' ' as u8 && ch <= '~' as u8 {
+        self.ascii.push(if (b' '..=b'~').contains(&ch) {
             ch as char
         } else {
             '.'