diff --git a/Cargo.toml b/Cargo.toml
index 68639a2..e9682b9 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "fitsrs"
-version = "0.2.9"
+version = "0.2.10"
 authors = ["Matthieu Baumann <matthieu.baumann@astro.unistra.fr>"]
 edition = "2018"
 description = "Implementation of the FITS image parser"
diff --git a/src/error.rs b/src/error.rs
index 01d93b9..621e334 100644
--- a/src/error.rs
+++ b/src/error.rs
@@ -19,6 +19,9 @@ quick_error! {
         ValueBadParsing {
             display("A value could not be parsed correctly")
         }
+        FailTypeCardParsing(card: String, t: String) {
+            display("{} card is not of type {}", card, t)
+        }
         NotSupportedXtensionType(extension: String) {
             display("`{}` extension is not supported. Only BINTABLE, TABLE and IMAGE are.", extension)
         }
@@ -31,4 +34,4 @@ quick_error! {
             display("Fail to parse a keyword as a utf8 string")
         }
     }
-}
\ No newline at end of file
+}
diff --git a/src/hdu/data/asciitable.rs b/src/hdu/data/asciitable.rs
index 97893d2..69b4e39 100644
--- a/src/hdu/data/asciitable.rs
+++ b/src/hdu/data/asciitable.rs
@@ -38,10 +38,10 @@ where
 
         let bytes = &bytes[start_byte_pos..end_byte_pos];
 
-        let w = bytes as *const [u8] as *mut UnsafeCell<[u8]>;
+        let c = bytes as *const [u8] as *mut UnsafeCell<[u8]>;
         unsafe {
-            let word: &UnsafeCell<[u8]> = &*w;
-            let x_mut_ref = &mut *word.get();
+            let cell: &UnsafeCell<[u8]> = &*c;
+            let x_mut_ref = &mut *cell.get();
 
             let (_, data, _) = x_mut_ref.align_to_mut::<u8>();
             let data = &data[..num_bytes_read];
diff --git a/src/hdu/data/bintable.rs b/src/hdu/data/bintable.rs
index 31ad8a0..0cd7dd4 100644
--- a/src/hdu/data/bintable.rs
+++ b/src/hdu/data/bintable.rs
@@ -38,10 +38,10 @@ where
 
         let bytes = &bytes[start_byte_pos..end_byte_pos];
 
-        let w = bytes as *const [u8] as *mut UnsafeCell<[u8]>;
+        let c = bytes as *const [u8] as *mut UnsafeCell<[u8]>;
         unsafe {
-            let word: &UnsafeCell<[u8]> = &*w;
-            let x_mut_ref = &mut *word.get();
+            let cell: &UnsafeCell<[u8]> = &*c;
+            let x_mut_ref = &mut *cell.get();
 
             let (_, data, _) = x_mut_ref.align_to_mut::<u8>();
             let data = &data[..num_bytes_read];
diff --git a/src/hdu/data/image.rs b/src/hdu/data/image.rs
index b8aabcd..7043bf0 100644
--- a/src/hdu/data/image.rs
+++ b/src/hdu/data/image.rs
@@ -40,11 +40,10 @@ where
 
         let bytes = &bytes[start_byte_pos..end_byte_pos];
 
-        let w = bytes as *const [u8] as *mut UnsafeCell<[u8]>;
-        //let x_ptr = UnsafeCell::new(bytes as *const [u8] as *mut [u8];
+        let c = bytes as *const [u8] as *mut UnsafeCell<[u8]>;
         unsafe {
-            let word: &UnsafeCell<[u8]> = &*w;
-            let x_mut_ref = &mut *word.get();
+            let cell: &UnsafeCell<[u8]> = &*c;
+            let x_mut_ref = &mut *cell.get();
 
             match bitpix {
                 BitpixValue::U8 => {
diff --git a/src/hdu/header/mod.rs b/src/hdu/header/mod.rs
index dfc8057..b4cf9df 100644
--- a/src/hdu/header/mod.rs
+++ b/src/hdu/header/mod.rs
@@ -53,7 +53,7 @@ fn parse_generic_card(card: &[u8; 80]) -> Result<Option<Card>, Error> {
         b"HISTORY " => {
             let v = Value::String(String::from_utf8_lossy(&card[8..]).to_string());
             Some(v)
-        },
+        }
         _ => {
             let str = String::from_utf8_lossy(&card[8..]);
             // Take until the comment beginning with '/'
@@ -70,9 +70,9 @@ fn parse_generic_card(card: &[u8; 80]) -> Result<Option<Card>, Error> {
                     &str
                 };
 
-                // remove the ' ' before and after 
+                // remove the ' ' before and after
                 let str = str.trim();
-                
+
                 if str.is_empty() {
                     Value::Undefined
                 } else if let Ok(val) = str.parse::<f64>() {
@@ -86,7 +86,7 @@ fn parse_generic_card(card: &[u8; 80]) -> Result<Option<Card>, Error> {
                 } else {
                     // Last case check for a string
                     let inside_str = str.split('\'').collect::<Vec<_>>();
-                    
+
                     if inside_str.len() >= 2 {
                         // This is a true string because it is nested inside simple quotes
                         Value::String(inside_str[1].to_string())
@@ -119,10 +119,14 @@ pub fn check_card_keyword(card: &[u8; 80], keyword: &[u8; 8]) -> Result<card::Va
         if &kw == keyword {
             Ok(v)
         } else {
-            Err(Error::FailFindingKeyword(std::str::from_utf8(keyword)?.to_owned()))
+            Err(Error::FailFindingKeyword(
+                std::str::from_utf8(keyword)?.to_owned(),
+            ))
         }
     } else {
-        Err(Error::FailFindingKeyword(std::str::from_utf8(keyword)?.to_owned()))
+        Err(Error::FailFindingKeyword(
+            std::str::from_utf8(keyword)?.to_owned(),
+        ))
     }
 }
 
@@ -145,7 +149,14 @@ fn parse_naxis_card(card: &[u8; 80]) -> Result<usize, Error> {
     Ok(naxis as usize)
 }
 
-const NAXIS_KW: [&[u8; 8]; 6] = [b"NAXIS1  ", b"NAXIS2  ", b"NAXIS3  ", b"NAXIS4  ", b"NAXIS5  ", b"NAXIS6  "];
+const NAXIS_KW: [&[u8; 8]; 6] = [
+    b"NAXIS1  ",
+    b"NAXIS2  ",
+    b"NAXIS3  ",
+    b"NAXIS4  ",
+    b"NAXIS5  ",
+    b"NAXIS6  ",
+];
 
 #[derive(Debug, PartialEq, Serialize, Clone, Copy)]
 pub enum BitpixValue {
@@ -167,7 +178,7 @@ pub(crate) fn parse_card_value(buf: &[u8]) -> IResult<&[u8], Value> {
                     parse_character_string,
                     parse_logical,
                     parse_float,
-                    parse_integer
+                    parse_integer,
                 )),
             ),
             parse_undefined,
@@ -259,8 +270,12 @@ where
     where
         T: CardValue,
     {
-        self.get(key)
-            .map(|value| <T as CardValue>::parse(value.clone()))
+        self.get(key).map(|value| {
+            <T as CardValue>::parse(value.clone()).map_err(|e| {
+                let card = String::from_utf8_lossy(key);
+                Error::FailTypeCardParsing(card.to_string(), std::any::type_name::<T>().to_string())
+            })
+        })
     }
 }