auto merge of #16291 : nham/rust/byte_literals, r=alexcrichton

This replaces many instances chars being casted to u8 with byte literals.

Author: bors

src/libcollections/str.rs

@@ -1457,7 +1457,7 @@ mod tests {
             109
         ];
         assert_eq!("".as_bytes(), &[]);
-        assert_eq!("abc".as_bytes(), &['a' as u8, 'b' as u8, 'c' as u8]);
+        assert_eq!("abc".as_bytes(), b"abc");
         assert_eq!("ศไทย中华Việt Nam".as_bytes(), v.as_slice());
     }
 
@@ -1475,11 +1475,11 @@ mod tests {
     fn test_as_ptr() {
         let buf = "hello".as_ptr();
         unsafe {
-            assert_eq!(*buf.offset(0), 'h' as u8);
-            assert_eq!(*buf.offset(1), 'e' as u8);
-            assert_eq!(*buf.offset(2), 'l' as u8);
-            assert_eq!(*buf.offset(3), 'l' as u8);
-            assert_eq!(*buf.offset(4), 'o' as u8);
+            assert_eq!(*buf.offset(0), b'h');
+            assert_eq!(*buf.offset(1), b'e');
+            assert_eq!(*buf.offset(2), b'l');
+            assert_eq!(*buf.offset(3), b'l');
+            assert_eq!(*buf.offset(4), b'o');
         }
     }
 

src/libcollections/string.rs

@@ -1040,7 +1040,7 @@ mod tests {
     fn test_push_bytes() {
         let mut s = String::from_str("ABC");
         unsafe {
-            s.push_bytes([ 'D' as u8 ]);
+            s.push_bytes([b'D']);
         }
         assert_eq!(s.as_slice(), "ABCD");
     }

src/libcore/fmt/float.rs

@@ -198,11 +198,11 @@ pub fn float_to_str_bytes_common<T: Primitive + Float, U>(
     // Decide what sign to put in front
     match sign {
         SignNeg | SignAll if neg => {
-            buf[end] = '-' as u8;
+            buf[end] = b'-';
             end += 1;
         }
         SignAll => {
-            buf[end] = '+' as u8;
+            buf[end] = b'+';
             end += 1;
         }
         _ => ()
@@ -218,7 +218,7 @@ pub fn float_to_str_bytes_common<T: Primitive + Float, U>(
     // Now emit the fractional part, if any
     deccum = num.fract();
     if deccum != _0 || (limit_digits && exact && digit_count > 0) {
-        buf[end] = '.' as u8;
+        buf[end] = b'.';
         end += 1;
         let mut dig = 0u;
 
@@ -269,8 +269,8 @@ pub fn float_to_str_bytes_common<T: Primitive + Float, U>(
                     // If reached left end of number, have to
                     // insert additional digit:
                     if i < 0
-                    || buf[i as uint] == '-' as u8
-                    || buf[i as uint] == '+' as u8 {
+                    || buf[i as uint] == b'-'
+                    || buf[i as uint] == b'+' {
                         for j in range(i as uint + 1, end).rev() {
                             buf[j + 1] = buf[j];
                         }
@@ -280,7 +280,7 @@ pub fn float_to_str_bytes_common<T: Primitive + Float, U>(
                     }
 
                     // Skip the '.'
-                    if buf[i as uint] == '.' as u8 { i -= 1; continue; }
+                    if buf[i as uint] == b'.' { i -= 1; continue; }
 
                     // Either increment the digit,
                     // or set to 0 if max and carry the 1.
@@ -306,14 +306,14 @@ pub fn float_to_str_bytes_common<T: Primitive + Float, U>(
         let mut i = buf_max_i;
 
         // discover trailing zeros of fractional part
-        while i > start_fractional_digits && buf[i] == '0' as u8 {
+        while i > start_fractional_digits && buf[i] == b'0' {
             i -= 1;
         }
 
         // Only attempt to truncate digits if buf has fractional digits
         if i >= start_fractional_digits {
             // If buf ends with '.', cut that too.
-            if buf[i] == '.' as u8 { i -= 1 }
+            if buf[i] == b'.' { i -= 1 }
 
             // only resize buf if we actually remove digits
             if i < buf_max_i {
@@ -323,7 +323,7 @@ pub fn float_to_str_bytes_common<T: Primitive + Float, U>(
     } // If exact and trailing '.', just cut that
     else {
         let max_i = end - 1;
-        if buf[max_i] == '.' as u8 {
+        if buf[max_i] == b'.' {
             end = max_i;
         }
     }

src/libcore/fmt/num.rs

@@ -104,13 +104,13 @@ macro_rules! radix {
     }
 }
 
-radix!(Binary,    2, "0b", x @  0 .. 2 => '0' as u8 + x)
-radix!(Octal,     8, "0o", x @  0 .. 7 => '0' as u8 + x)
-radix!(Decimal,  10, "",   x @  0 .. 9 => '0' as u8 + x)
-radix!(LowerHex, 16, "0x", x @  0 .. 9 => '0' as u8 + x,
-                           x @ 10 ..15 => 'a' as u8 + (x - 10))
-radix!(UpperHex, 16, "0x", x @  0 .. 9 => '0' as u8 + x,
-                           x @ 10 ..15 => 'A' as u8 + (x - 10))
+radix!(Binary,    2, "0b", x @  0 .. 2 => b'0' + x)
+radix!(Octal,     8, "0o", x @  0 .. 7 => b'0' + x)
+radix!(Decimal,  10, "",   x @  0 .. 9 => b'0' + x)
+radix!(LowerHex, 16, "0x", x @  0 .. 9 => b'0' + x,
+                           x @ 10 ..15 => b'a' + (x - 10))
+radix!(UpperHex, 16, "0x", x @  0 .. 9 => b'0' + x,
+                           x @ 10 ..15 => b'A' + (x - 10))
 
 /// A radix with in the range of `2..36`.
 #[deriving(Clone, PartialEq)]
@@ -129,8 +129,8 @@ impl GenericRadix for Radix {
     fn base(&self) -> u8 { self.base }
     fn digit(&self, x: u8) -> u8 {
         match x {
-            x @  0 ..9 => '0' as u8 + x,
-            x if x < self.base() => 'a' as u8 + (x - 10),
+            x @  0 ..9 => b'0' + x,
+            x if x < self.base() => b'a' + (x - 10),
             x => fail!("number not in the range 0..{}: {}", self.base() - 1, x),
         }
     }

src/libcore/str.rs

@@ -1755,7 +1755,7 @@ impl<'a> StrSlice<'a> for &'a str {
     fn lines_any(&self) -> AnyLines<'a> {
         self.lines().map(|line| {
             let l = line.len();
-            if l > 0 && line.as_bytes()[l - 1] == '\r' as u8 { line.slice(0, l - 1) }
+            if l > 0 && line.as_bytes()[l - 1] == b'\r' { line.slice(0, l - 1) }
             else { line }
         })
     }

src/libdebug/repr.rs

@@ -165,11 +165,11 @@ impl<'a> ReprVisitor<'a> {
     }
 
     pub fn write_escaped_slice(&mut self, slice: &str) -> bool {
-        try!(self, self.writer.write(['"' as u8]));
+        try!(self, self.writer.write([b'"']));
         for ch in slice.chars() {
             if !self.write_escaped_char(ch, true) { return false }
         }
-        try!(self, self.writer.write(['"' as u8]));
+        try!(self, self.writer.write([b'"']));
         true
     }
 
@@ -188,7 +188,7 @@ impl<'a> ReprVisitor<'a> {
                            inner: *const TyDesc) -> bool {
         let mut p = ptr as *const u8;
         let (sz, al) = unsafe { ((*inner).size, (*inner).align) };
-        try!(self, self.writer.write(['[' as u8]));
+        try!(self, self.writer.write([b'[']));
         let mut first = true;
         let mut left = len;
         // unit structs have 0 size, and don't loop forever.
@@ -203,7 +203,7 @@ impl<'a> ReprVisitor<'a> {
             p = align(unsafe { p.offset(sz as int) as uint }, al) as *const u8;
             left -= dec;
         }
-        try!(self, self.writer.write([']' as u8]));
+        try!(self, self.writer.write([b']']));
         true
     }
 
@@ -263,9 +263,9 @@ impl<'a> TyVisitor for ReprVisitor<'a> {
 
     fn visit_char(&mut self) -> bool {
         self.get::<char>(|this, &ch| {
-            try!(this, this.writer.write(['\'' as u8]));
+            try!(this, this.writer.write([b'\'']));
             if !this.write_escaped_char(ch, false) { return false }
-            try!(this, this.writer.write(['\'' as u8]));
+            try!(this, this.writer.write([b'\'']));
             true
         })
     }
@@ -310,7 +310,7 @@ impl<'a> TyVisitor for ReprVisitor<'a> {
     }
 
     fn visit_rptr(&mut self, mtbl: uint, inner: *const TyDesc) -> bool {
-        try!(self, self.writer.write(['&' as u8]));
+        try!(self, self.writer.write([b'&']));
         self.write_mut_qualifier(mtbl);
         self.get::<*const u8>(|this, p| {
             this.visit_ptr_inner(*p, inner)
@@ -319,7 +319,7 @@ impl<'a> TyVisitor for ReprVisitor<'a> {
 
     fn visit_evec_slice(&mut self, mtbl: uint, inner: *const TyDesc) -> bool {
         self.get::<raw::Slice<()>>(|this, s| {
-            try!(this, this.writer.write(['&' as u8]));
+            try!(this, this.writer.write([b'&']));
             this.write_mut_qualifier(mtbl);
             let size = unsafe {
                 if (*inner).size == 0 { 1 } else { (*inner).size }
@@ -338,7 +338,7 @@ impl<'a> TyVisitor for ReprVisitor<'a> {
 
     fn visit_enter_rec(&mut self, _n_fields: uint,
                        _sz: uint, _align: uint) -> bool {
-        try!(self, self.writer.write(['{' as u8]));
+        try!(self, self.writer.write([b'{']));
         true
     }
 
@@ -356,7 +356,7 @@ impl<'a> TyVisitor for ReprVisitor<'a> {
 
     fn visit_leave_rec(&mut self, _n_fields: uint,
                        _sz: uint, _align: uint) -> bool {
-        try!(self, self.writer.write(['}' as u8]));
+        try!(self, self.writer.write([b'}']));
         true
     }
 
@@ -365,9 +365,9 @@ impl<'a> TyVisitor for ReprVisitor<'a> {
         try!(self, self.writer.write(name.as_bytes()));
         if n_fields != 0 {
             if named_fields {
-                try!(self, self.writer.write(['{' as u8]));
+                try!(self, self.writer.write([b'{']));
             } else {
-                try!(self, self.writer.write(['(' as u8]));
+                try!(self, self.writer.write([b'(']));
             }
         }
         true
@@ -390,17 +390,17 @@ impl<'a> TyVisitor for ReprVisitor<'a> {
                          _sz: uint, _align: uint) -> bool {
         if n_fields != 0 {
             if named_fields {
-                try!(self, self.writer.write(['}' as u8]));
+                try!(self, self.writer.write([b'}']));
             } else {
-                try!(self, self.writer.write([')' as u8]));
+                try!(self, self.writer.write([b')']));
             }
         }
         true
     }
 
     fn visit_enter_tup(&mut self, _n_fields: uint,
                        _sz: uint, _align: uint) -> bool {
-        try!(self, self.writer.write(['(' as u8]));
+        try!(self, self.writer.write([b'(']));
         true
     }
 
@@ -415,9 +415,9 @@ impl<'a> TyVisitor for ReprVisitor<'a> {
     fn visit_leave_tup(&mut self, _n_fields: uint,
                        _sz: uint, _align: uint) -> bool {
         if _n_fields == 1 {
-            try!(self, self.writer.write([',' as u8]));
+            try!(self, self.writer.write([b',']));
         }
-        try!(self, self.writer.write([')' as u8]));
+        try!(self, self.writer.write([b')']));
         true
     }
 
@@ -455,7 +455,7 @@ impl<'a> TyVisitor for ReprVisitor<'a> {
         if write {
             try!(self, self.writer.write(name.as_bytes()));
             if n_fields > 0 {
-                try!(self, self.writer.write(['(' as u8]));
+                try!(self, self.writer.write([b'(']));
             }
         }
         true
@@ -487,7 +487,7 @@ impl<'a> TyVisitor for ReprVisitor<'a> {
         match self.var_stk[self.var_stk.len() - 1] {
             Matched => {
                 if n_fields > 0 {
-                    try!(self, self.writer.write([')' as u8]));
+                    try!(self, self.writer.write([b')']));
                 }
             }
             _ => ()

src/libgetopts/lib.rs

@@ -372,7 +372,7 @@ impl Matches {
 }
 
 fn is_arg(arg: &str) -> bool {
-    arg.len() > 1 && arg.as_bytes()[0] == '-' as u8
+    arg.len() > 1 && arg.as_bytes()[0] == b'-'
 }
 
 fn find_opt(opts: &[Opt], nm: Name) -> Option<uint> {
@@ -555,7 +555,7 @@ pub fn getopts(args: &[String], optgrps: &[OptGroup]) -> Result {
         } else {
             let mut names;
             let mut i_arg = None;
-            if cur.as_bytes()[1] == '-' as u8 {
+            if cur.as_bytes()[1] == b'-' {
                 let tail = cur.as_slice().slice(2, curlen);
                 let tail_eq: Vec<&str> = tail.split('=').collect();
                 if tail_eq.len() <= 1 {

src/libnum/bigint.rs

@@ -1376,7 +1376,7 @@ impl BigInt {
         if buf.is_empty() { return None; }
         let mut sign  = Plus;
         let mut start = 0;
-        if buf[0] == ('-' as u8) {
+        if buf[0] == b'-' {
             sign  = Minus;
             start = 1;
         }

src/libregex/test/bench.rs

@@ -159,7 +159,7 @@ fn gen_text(n: uint) -> String {
                        .collect::<Vec<u8>>();
     for (i, b) in bytes.mut_iter().enumerate() {
         if i % 20 == 0 {
-            *b = '\n' as u8
+            *b = b'\n'
         }
     }
     String::from_utf8(bytes).unwrap()

src/libserialize/base64.rs

@@ -89,8 +89,8 @@ impl<'a> ToBase64 for &'a [u8] {
             match config.line_length {
                 Some(line_length) =>
                     if cur_length >= line_length {
-                        v.push('\r' as u8);
-                        v.push('\n' as u8);
+                        v.push(b'\r');
+                        v.push(b'\n');
                         cur_length = 0;
                     },
                 None => ()
@@ -114,8 +114,8 @@ impl<'a> ToBase64 for &'a [u8] {
             match config.line_length {
                 Some(line_length) =>
                     if cur_length >= line_length {
-                        v.push('\r' as u8);
-                        v.push('\n' as u8);
+                        v.push(b'\r');
+                        v.push(b'\n');
                     },
                 None => ()
             }
@@ -130,8 +130,8 @@ impl<'a> ToBase64 for &'a [u8] {
                 v.push(bytes[((n >> 18) & 63) as uint]);
                 v.push(bytes[((n >> 12) & 63) as uint]);
                 if config.pad {
-                    v.push('=' as u8);
-                    v.push('=' as u8);
+                    v.push(b'=');
+                    v.push(b'=');
                 }
             }
             2 => {
@@ -141,7 +141,7 @@ impl<'a> ToBase64 for &'a [u8] {
                 v.push(bytes[((n >> 12) & 63) as uint]);
                 v.push(bytes[((n >> 6 ) & 63) as uint]);
                 if config.pad {
-                    v.push('=' as u8);
+                    v.push(b'=');
                 }
             }
             _ => fail!("Algebra is broken, please alert the math police")

src/libserialize/hex.rs

@@ -112,11 +112,11 @@ impl<'a> FromHex for &'a str {
         for (idx, byte) in self.bytes().enumerate() {
             buf <<= 4;
 
-            match byte as char {
-                'A'..'F' => buf |= byte - ('A' as u8) + 10,
-                'a'..'f' => buf |= byte - ('a' as u8) + 10,
-                '0'..'9' => buf |= byte - ('0' as u8),
-                ' '|'\r'|'\n'|'\t' => {
+            match byte {
+                b'A'..b'F' => buf |= byte - b'A' + 10,
+                b'a'..b'f' => buf |= byte - b'a' + 10,
+                b'0'..b'9' => buf |= byte - b'0',
+                b' '|b'\r'|b'\n'|b'\t' => {
                     buf >>= 4;
                     continue
                 }