implement raw strings (r#"foo"#)

doc/rust.md

@@ -239,13 +239,14 @@ literal : string_lit | char_lit | num_lit ;
 
 ~~~~~~~~ {.ebnf .gram}
 char_lit : '\x27' char_body '\x27' ;
-string_lit : '"' string_body * '"' ;
+string_lit : '"' string_body * '"' | 'r' raw_string ;
 
 char_body : non_single_quote
           | '\x5c' [ '\x27' | common_escape ] ;
 
 string_body : non_double_quote
             | '\x5c' [ '\x22' | common_escape ] ;
+raw_string : '"' raw_string_body '"' | '#' raw_string '#' ;
 
 common_escape : '\x5c'
               | 'n' | 'r' | 't' | '0'
@@ -267,9 +268,10 @@ which must be _escaped_ by a preceding U+005C character (`\`).
 
 A _string literal_ is a sequence of any Unicode characters enclosed within
 two `U+0022` (double-quote) characters, with the exception of `U+0022`
-itself, which must be _escaped_ by a preceding `U+005C` character (`\`).
+itself, which must be _escaped_ by a preceding `U+005C` character (`\`),
+or a _raw string literal_.
 
-Some additional _escapes_ are available in either character or string
+Some additional _escapes_ are available in either character or non-raw string
 literals. An escape starts with a `U+005C` (`\`) and continues with one of
 the following forms:
 
@@ -285,9 +287,35 @@ the following forms:
   * A _whitespace escape_ is one of the characters `U+006E` (`n`), `U+0072`
     (`r`), or `U+0074` (`t`), denoting the unicode values `U+000A` (LF),
     `U+000D` (CR) or `U+0009` (HT) respectively.
-  * The _backslash escape_ is the character U+005C (`\`) which must be
+  * The _backslash escape_ is the character `U+005C` (`\`) which must be
     escaped in order to denote *itself*.
 
+Raw string literals do not process any escapes. They start with the character
+`U+0072` (`r`), followed zero or more of the character `U+0023` (`#`) and a
+`U+0022` (double-quote) character. The _raw string body_ is not defined in the
+EBNF grammar above: it can contain any sequence of Unicode characters and is
+terminated only by another `U+0022` (double-quote) character, followed by the
+same number of `U+0023` (`#`) characters that preceeded the opening `U+0022`
+(double-quote) character.
+
+All Unicode characters contained in the raw string body represent themselves,
+the characters `U+0022` (double-quote) (except when followed by at least as
+many `U+0023` (`#`) characters as were used to start the raw string literal) or
+`U+005C` (`\`) do not have any special meaning.
+
+Examples for string literals:
+
+~~~
+"foo"; r"foo";                     // foo
+"\"foo\""; r#""foo""#;             // "foo"
+
+"foo #\"# bar";
+r##"foo #"# bar"##;                // foo #"# bar
+
+"\x52"; "R"; r"R";                 // R
+"\\x52"; r"\x52";                  // \x52
+~~~
+
 #### Number literals
 
 ~~~~~~~~ {.ebnf .gram}

doc/tutorial.md

@@ -353,7 +353,12 @@ whose literals are written between single quotes, as in `'x'`.
 Just like C, Rust understands a number of character escapes, using the backslash
 character, such as `\n`, `\r`, and `\t`. String literals,
 written between double quotes, allow the same escape sequences.
-More on strings [later](#vectors-and-strings).
+
+On the other hand, raw string literals do not process any escape sequences.
+They are written as `r##"blah"##`, with a matching number of zero or more `#`
+before the opening and after the closing quote, and can contain any sequence of
+characters except their closing delimiter.  More on strings
+[later](#vectors-and-strings).
 
 The nil type, written `()`, has a single value, also written `()`.
 

src/etc/vim/syntax/rust.vim

@@ -148,6 +148,7 @@ syn match     rustFormat      display "%%" contained
 syn match     rustSpecial     display contained /\\\([nrt\\'"]\|x\x\{2}\|u\x\{4}\|U\x\{8}\)/
 syn match     rustStringContinuation display contained /\\\n\s*/
 syn region    rustString      start=+"+ skip=+\\\\\|\\"+ end=+"+ contains=rustTodo,rustFormat,rustSpecial,rustStringContinuation
+syn region    rustString      start='r\z(#*\)"' end='"\z1'
 
 syn region    rustAttribute   start="#\[" end="\]" contains=rustString,rustDeriving
 syn region    rustDeriving    start="deriving(" end=")" contained contains=rustTrait

src/librustc/front/test.rs

@@ -407,7 +407,7 @@ fn mk_test_desc_and_fn_rec(cx: &TestCtxt, test: &Test) -> @ast::Expr {
     debug2!("encoding {}", ast_util::path_name_i(path));
 
     let name_lit: ast::lit =
-        nospan(ast::lit_str(ast_util::path_name_i(path).to_managed()));
+        nospan(ast::lit_str(ast_util::path_name_i(path).to_managed(), ast::CookedStr));
 
     let name_expr = @ast::Expr {
           id: ast::DUMMY_NODE_ID,

src/librustc/metadata/creader.rs

@@ -142,7 +142,7 @@ fn visit_view_item(e: @mut Env, i: &ast::view_item) {
           let ident = token::ident_to_str(&ident);
           let meta_items = match path_opt {
               None => meta_items.clone(),
-              Some(p) => {
+              Some((p, _path_str_style)) => {
                   let p_path = Path(p);
                   match p_path.filestem() {
                       Some(s) =>

src/librustc/metadata/encoder.rs

@@ -1446,7 +1446,7 @@ fn encode_meta_item(ebml_w: &mut writer::Encoder, mi: @MetaItem) {
       }
       MetaNameValue(name, value) => {
         match value.node {
-          lit_str(value) => {
+          lit_str(value, _) => {
             ebml_w.start_tag(tag_meta_item_name_value);
             ebml_w.start_tag(tag_meta_item_name);
             ebml_w.writer.write(name.as_bytes());

src/librustc/middle/check_const.rs

@@ -86,7 +86,7 @@ pub fn check_pat(v: &mut CheckCrateVisitor, p: @Pat, _is_const: bool) {
         match e.node {
             ExprVstore(
                 @Expr { node: ExprLit(@codemap::Spanned {
-                    node: lit_str(_),
+                    node: lit_str(*),
                     _}),
                        _ },
                 ExprVstoreUniq
@@ -120,7 +120,7 @@ pub fn check_expr(v: &mut CheckCrateVisitor,
                           "disallowed operator in constant expression");
             return;
           }
-          ExprLit(@codemap::Spanned {node: lit_str(_), _}) => { }
+          ExprLit(@codemap::Spanned {node: lit_str(*), _}) => { }
           ExprBinary(*) | ExprUnary(*) => {
             if method_map.contains_key(&e.id) {
                 sess.span_err(e.span, "user-defined operators are not \

src/librustc/middle/const_eval.rs

@@ -475,7 +475,7 @@ pub fn eval_const_expr_partial<T: ty::ExprTyProvider>(tcx: &T, e: &Expr)
 
 pub fn lit_to_const(lit: &lit) -> const_val {
     match lit.node {
-      lit_str(s) => const_str(s),
+      lit_str(s, _) => const_str(s),
       lit_char(n) => const_uint(n as u64),
       lit_int(n, _) => const_int(n),
       lit_uint(n, _) => const_uint(n),

src/librustc/middle/trans/consts.rs

@@ -71,7 +71,7 @@ pub fn const_lit(cx: &mut CrateContext, e: &ast::Expr, lit: ast::lit)
       }
       ast::lit_bool(b) => C_bool(b),
       ast::lit_nil => C_nil(),
-      ast::lit_str(s) => C_estr_slice(cx, s)
+      ast::lit_str(s, _) => C_estr_slice(cx, s)
     }
 }
 

src/librustc/middle/trans/expr.rs

@@ -705,7 +705,7 @@ fn trans_rvalue_dps_unadjusted(bcx: @mut Block, expr: &ast::Expr,
                 args.iter().enumerate().map(|(i, arg)| (i, *arg)).collect();
             return trans_adt(bcx, repr, 0, numbered_fields, None, dest);
         }
-        ast::ExprLit(@codemap::Spanned {node: ast::lit_str(s), _}) => {
+        ast::ExprLit(@codemap::Spanned {node: ast::lit_str(s, _), _}) => {
             return tvec::trans_lit_str(bcx, expr, s, dest);
         }
         ast::ExprVstore(contents, ast::ExprVstoreSlice) |

src/librustc/middle/trans/tvec.rs

@@ -205,7 +205,7 @@ pub fn trans_slice_vstore(bcx: @mut Block,
 
     // Handle the &"..." case:
     match content_expr.node {
-        ast::ExprLit(@codemap::Spanned {node: ast::lit_str(s), span: _}) => {
+        ast::ExprLit(@codemap::Spanned {node: ast::lit_str(s, _), span: _}) => {
             return trans_lit_str(bcx, content_expr, s, dest);
         }
         _ => {}
@@ -296,7 +296,7 @@ pub fn trans_uniq_or_managed_vstore(bcx: @mut Block, heap: heap, vstore_expr: &a
         heap_exchange => {
             match content_expr.node {
                 ast::ExprLit(@codemap::Spanned {
-                    node: ast::lit_str(s), span
+                    node: ast::lit_str(s, _), span
                 }) => {
                     let llptrval = C_cstr(bcx.ccx(), s);
                     let llptrval = PointerCast(bcx, llptrval, Type::i8p());
@@ -357,7 +357,7 @@ pub fn write_content(bcx: @mut Block,
     let _indenter = indenter();
 
     match content_expr.node {
-        ast::ExprLit(@codemap::Spanned { node: ast::lit_str(s), _ }) => {
+        ast::ExprLit(@codemap::Spanned { node: ast::lit_str(s, _), _ }) => {
             match dest {
                 Ignore => {
                     return bcx;
@@ -490,7 +490,7 @@ pub fn elements_required(bcx: @mut Block, content_expr: &ast::Expr) -> uint {
     //! Figure out the number of elements we need to store this content
 
     match content_expr.node {
-        ast::ExprLit(@codemap::Spanned { node: ast::lit_str(s), _ }) => {
+        ast::ExprLit(@codemap::Spanned { node: ast::lit_str(s, _), _ }) => {
             s.len()
         },
         ast::ExprVec(ref es, _) => es.len(),

src/librustc/middle/ty.rs

@@ -3266,7 +3266,7 @@ pub fn expr_kind(tcx: ctxt,
         ast::ExprDoBody(*) |
         ast::ExprBlock(*) |
         ast::ExprRepeat(*) |
-        ast::ExprLit(@codemap::Spanned {node: lit_str(_), _}) |
+        ast::ExprLit(@codemap::Spanned {node: lit_str(*), _}) |
         ast::ExprVstore(_, ast::ExprVstoreSlice) |
         ast::ExprVstore(_, ast::ExprVstoreMutSlice) |
         ast::ExprVec(*) => {

src/librustc/middle/typeck/check/mod.rs

@@ -2259,7 +2259,7 @@ pub fn check_expr_with_unifier(fcx: @mut FnCtxt,
     match expr.node {
       ast::ExprVstore(ev, vst) => {
         let typ = match ev.node {
-          ast::ExprLit(@codemap::Spanned { node: ast::lit_str(_), _ }) => {
+          ast::ExprLit(@codemap::Spanned { node: ast::lit_str(*), _ }) => {
             let tt = ast_expr_vstore_to_vstore(fcx, ev, vst);
             ty::mk_estr(tcx, tt)
           }

src/librustdoc/clean.rs

@@ -1008,7 +1008,7 @@ impl Clean<ViewItemInner> for ast::view_item_ {
     fn clean(&self) -> ViewItemInner {
         match self {
             &ast::view_item_extern_mod(ref i, ref p, ref mi, ref id) =>
-                ExternMod(i.clean(), p.map(|x| x.to_owned()),  mi.clean(), *id),
+                ExternMod(i.clean(), p.map(|&(ref x, _)| x.to_owned()),  mi.clean(), *id),
             &ast::view_item_use(ref vp) => Import(vp.clean())
         }
     }
@@ -1114,7 +1114,7 @@ impl ToSource for syntax::codemap::Span {
 
 fn lit_to_str(lit: &ast::lit) -> ~str {
     match lit.node {
-        ast::lit_str(st) => st.to_owned(),
+        ast::lit_str(st, _) => st.to_owned(),
         ast::lit_char(c) => ~"'" + std::char::from_u32(c).unwrap().to_str() + "'",
         ast::lit_int(i, _t) => i.to_str(),
         ast::lit_uint(u, _t) => u.to_str(),

src/librustpkg/util.rs

@@ -406,7 +406,7 @@ impl<'self> Visitor<()> for ViewItemVisitor<'self> {
             // ignore metadata, I guess
             ast::view_item_extern_mod(lib_ident, path_opt, _, _) => {
                 let lib_name = match path_opt {
-                    Some(p) => p,
+                    Some((p, _)) => p,
                     None => self.sess.str_of(lib_ident)
                 };
                 debug2!("Finding and installing... {}", lib_name);
@@ -513,7 +513,7 @@ pub fn find_and_install_dependencies(context: &BuildContext,
 
 pub fn mk_string_lit(s: @str) -> ast::lit {
     Spanned {
-        node: ast::lit_str(s),
+        node: ast::lit_str(s, ast::CookedStr),
         span: dummy_sp()
     }
 }

src/libsyntax/ast.rs

@@ -680,11 +680,17 @@ pub enum mac_ {
     mac_invoc_tt(Path,~[token_tree],SyntaxContext),   // new macro-invocation
 }
 
+#[deriving(Clone, Eq, Encodable, Decodable, IterBytes)]
+pub enum StrStyle {
+    CookedStr,
+    RawStr(uint)
+}
+
 pub type lit = Spanned<lit_>;
 
 #[deriving(Clone, Eq, Encodable, Decodable, IterBytes)]
 pub enum lit_ {
-    lit_str(@str),
+    lit_str(@str, StrStyle),
     lit_char(u32),
     lit_int(i64, int_ty),
     lit_uint(u64, uint_ty),
@@ -862,6 +868,7 @@ pub enum asm_dialect {
 #[deriving(Clone, Eq, Encodable, Decodable, IterBytes)]
 pub struct inline_asm {
     asm: @str,
+    asm_str_style: StrStyle,
     clobbers: @str,
     inputs: ~[(@str, @Expr)],
     outputs: ~[(@str, @Expr)],
@@ -1027,7 +1034,7 @@ pub enum view_item_ {
     // optional @str: if present, this is a location (containing
     // arbitrary characters) from which to fetch the crate sources
     // For example, extern mod whatever = "github.com/mozilla/rust"
-    view_item_extern_mod(Ident, Option<@str>, ~[@MetaItem], NodeId),
+    view_item_extern_mod(Ident, Option<(@str, StrStyle)>, ~[@MetaItem], NodeId),
     view_item_use(~[@view_path]),
 }
 

src/libsyntax/attr.rs

@@ -67,7 +67,7 @@ impl AttrMetaMethods for MetaItem {
         match self.node {
             MetaNameValue(_, ref v) => {
                 match v.node {
-                    ast::lit_str(s) => Some(s),
+                    ast::lit_str(s, _) => Some(s),
                     _ => None,
                 }
             },
@@ -127,7 +127,7 @@ impl AttributeMethods for Attribute {
 /* Constructors */
 
 pub fn mk_name_value_item_str(name: @str, value: @str) -> @MetaItem {
-    let value_lit = dummy_spanned(ast::lit_str(value));
+    let value_lit = dummy_spanned(ast::lit_str(value, ast::CookedStr));
     mk_name_value_item(name, value_lit)
 }
 
@@ -153,7 +153,7 @@ pub fn mk_attr(item: @MetaItem) -> Attribute {
 
 pub fn mk_sugared_doc_attr(text: @str, lo: BytePos, hi: BytePos) -> Attribute {
     let style = doc_comment_style(text);
-    let lit = spanned(lo, hi, ast::lit_str(text));
+    let lit = spanned(lo, hi, ast::lit_str(text, ast::CookedStr));
     let attr = Attribute_ {
         style: style,
         value: @spanned(lo, hi, MetaNameValue(@"doc", lit)),

src/libsyntax/ext/asm.rs

@@ -44,6 +44,7 @@ pub fn expand_asm(cx: @ExtCtxt, sp: Span, tts: &[ast::token_tree])
                                        tts.to_owned());
 
     let mut asm = @"";
+    let mut asm_str_style = None;
     let mut outputs = ~[];
     let mut inputs = ~[];
     let mut cons = ~"";
@@ -58,8 +59,11 @@ pub fn expand_asm(cx: @ExtCtxt, sp: Span, tts: &[ast::token_tree])
     while continue_ {
         match state {
             Asm => {
-                asm = expr_to_str(cx, p.parse_expr(),
-                                  "inline assembly must be a string literal.");
+                let (s, style) =
+                    expr_to_str(cx, p.parse_expr(),
+                                "inline assembly must be a string literal.");
+                asm = s;
+                asm_str_style = Some(style);
             }
             Outputs => {
                 while *p.token != token::EOF &&
@@ -70,7 +74,7 @@ pub fn expand_asm(cx: @ExtCtxt, sp: Span, tts: &[ast::token_tree])
                         p.eat(&token::COMMA);
                     }
 
-                    let constraint = p.parse_str();
+                    let (constraint, _str_style) = p.parse_str();
                     p.expect(&token::LPAREN);
                     let out = p.parse_expr();
                     p.expect(&token::RPAREN);
@@ -93,7 +97,7 @@ pub fn expand_asm(cx: @ExtCtxt, sp: Span, tts: &[ast::token_tree])
                         p.eat(&token::COMMA);
                     }
 
-                    let constraint = p.parse_str();
+                    let (constraint, _str_style) = p.parse_str();
                     p.expect(&token::LPAREN);
                     let input = p.parse_expr();
                     p.expect(&token::RPAREN);
@@ -111,14 +115,15 @@ pub fn expand_asm(cx: @ExtCtxt, sp: Span, tts: &[ast::token_tree])
                         p.eat(&token::COMMA);
                     }
 
-                    let clob = format!("~\\{{}\\}", p.parse_str());
+                    let (s, _str_style) = p.parse_str();
+                    let clob = format!("~\\{{}\\}", s);
                     clobs.push(clob);
                 }
 
                 cons = clobs.connect(",");
             }
             Options => {
-                let option = p.parse_str();
+                let (option, _str_style) = p.parse_str();
 
                 if "volatile" == option {
                     volatile = true;
@@ -175,6 +180,7 @@ pub fn expand_asm(cx: @ExtCtxt, sp: Span, tts: &[ast::token_tree])
         id: ast::DUMMY_NODE_ID,
         node: ast::ExprInlineAsm(ast::inline_asm {
             asm: asm,
+            asm_str_style: asm_str_style.unwrap(),
             clobbers: cons.to_managed(),
             inputs: inputs,
             outputs: outputs,