add new enum ast::StrStyle as field to ast::lit_str

For the benefit of the pretty printer we want to keep track of how
string literals in the ast were originally represented in the source
code.

This commit changes parser functions so they don't extract strings from
the token stream without at least also returning what style of string
literal it was. This is stored in the resulting ast node for string
literals, obviously, for the package id in `extern mod = r"package id"`
view items, for the inline asm in `asm!()` invocations.

For `asm!()`'s other arguments or for `extern "Rust" fn()` items, I just
the style of string, because it seemed disproportionally cumbersome to
thread that information through the string processing that happens with
those string literals, given the limited advantage raw string literals
would provide in these positions.

The other syntax extensions don't seem to store passed string literals
in the ast, so they also discard the style of strings they parse.

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,

src/libsyntax/ext/base.rs

@@ -410,10 +410,10 @@ impl ExtCtxt {
     }
 }
 
-pub fn expr_to_str(cx: @ExtCtxt, expr: @ast::Expr, err_msg: &str) -> @str {
+pub fn expr_to_str(cx: @ExtCtxt, expr: @ast::Expr, err_msg: &str) -> (@str, ast::StrStyle) {
     match expr.node {
       ast::ExprLit(l) => match l.node {
-        ast::lit_str(s) => s,
+        ast::lit_str(s, style) => (s, style),
         _ => cx.span_fatal(l.span, err_msg)
       },
       _ => cx.span_fatal(expr.span, err_msg)

src/libsyntax/ext/build.rs

@@ -562,7 +562,7 @@ impl AstBuilder for @ExtCtxt {
         self.expr_vstore(sp, self.expr_vec(sp, exprs), ast::ExprVstoreSlice)
     }
     fn expr_str(&self, sp: Span, s: @str) -> @ast::Expr {
-        self.expr_lit(sp, ast::lit_str(s))
+        self.expr_lit(sp, ast::lit_str(s, ast::CookedStr))
     }
     fn expr_str_uniq(&self, sp: Span, s: @str) -> @ast::Expr {
         self.expr_vstore(sp, self.expr_str(sp, s), ast::ExprVstoreUniq)

src/libsyntax/ext/bytes.rs

@@ -28,7 +28,7 @@ pub fn expand_syntax_ext(cx: @ExtCtxt, sp: Span, tts: &[ast::token_tree]) -> bas
             // expression is a literal
             ast::ExprLit(lit) => match lit.node {
                 // string literal, push each byte to vector expression
-                ast::lit_str(s) => {
+                ast::lit_str(s, _) => {
                     for byte in s.byte_iter() {
                         bytes.push(cx.expr_u8(expr.span, byte));
                     }

src/libsyntax/ext/deriving/generic.rs

@@ -361,7 +361,7 @@ impl<'self> TraitDef<'self> {
             span,
             cx.meta_name_value(span,
                                @"doc",
-                               ast::lit_str(@"Automatically derived.")));
+                               ast::lit_str(@"Automatically derived.", ast::CookedStr)));
         cx.item(
             span,
             ::parse::token::special_idents::clownshoes_extensions,

src/libsyntax/ext/env.rs

@@ -41,10 +41,13 @@ pub fn expand_env(cx: @ExtCtxt, sp: Span, tts: &[ast::token_tree])
         cx.span_fatal(sp, "env! takes 1 or 2 arguments");
     }
 
-    let var = expr_to_str(cx, exprs[0], "expected string literal");
+    let (var, _var_str_style) = expr_to_str(cx, exprs[0], "expected string literal");
     let msg = match exprs.len() {
         1 => format!("Environment variable {} not defined", var).to_managed(),
-        2 => expr_to_str(cx, exprs[1], "expected string literal"),
+        2 => {
+            let (s, _style) = expr_to_str(cx, exprs[1], "expected string literal");
+            s
+        }
         _ => cx.span_fatal(sp, "env! takes 1 or 2 arguments")
     };
 

src/libsyntax/ext/fmt.rs

@@ -30,7 +30,7 @@ pub fn expand_syntax_ext(cx: @ExtCtxt, sp: Span, tts: &[ast::token_tree])
     if args.len() == 0 {
         cx.span_fatal(sp, "fmt! takes at least 1 argument.");
     }
-    let fmt =
+    let (fmt, _fmt_str_style) =
         expr_to_str(cx, args[0],
                     "first argument to fmt! must be a string literal.");
     let fmtspan = args[0].span;

src/libsyntax/ext/format.rs

@@ -722,8 +722,8 @@ pub fn expand_args(ecx: @ExtCtxt, sp: Span,
         (_, None) => { return MRExpr(ecx.expr_uint(sp, 2)); }
     };
     cx.fmtsp = efmt.span;
-    let fmt = expr_to_str(ecx, efmt,
-                          "format argument must be a string literal.");
+    let (fmt, _fmt_str_style) = expr_to_str(ecx, efmt,
+                                            "format argument must be a string literal.");
 
     let mut err = false;
     do parse::parse_error::cond.trap(|m| {

src/libsyntax/ext/quote.rs

@@ -118,7 +118,7 @@ pub mod rt {
 
     impl<'self> ToSource for &'self str {
         fn to_source(&self) -> @str {
-            let lit = dummy_spanned(ast::lit_str(self.to_managed()));
+            let lit = dummy_spanned(ast::lit_str(self.to_managed(), ast::CookedStr));
             pprust::lit_to_str(@lit).to_managed()
         }
     }