Lexers now emit spans, not chposes.

5 files changed, 62 insertions, 48 deletions

diff --git a/src/libsyntax/ast.rs b/src/libsyntax/ast.rs
index ce674f53662..5f2a5b2accb 100644
--- a/src/libsyntax/ast.rs
+++ b/src/libsyntax/ast.rs
@@ -377,7 +377,7 @@ enum blk_sort {
 enum token_tree {
     /* for macro invocations; parsing is the macro's job */
     tt_delim([token_tree]),
-    tt_flat(uint, token::token)
+    tt_flat(span, token::token)
 }
 
 #[auto_serialize]
diff --git a/src/libsyntax/parse/comments.rs b/src/libsyntax/parse/comments.rs
index 53a6238d57f..69aa4775e43 100644
--- a/src/libsyntax/parse/comments.rs
+++ b/src/libsyntax/parse/comments.rs
@@ -1,7 +1,7 @@
 import io::reader_util;
 import io::println;//XXXXXXXXxxx
 import util::interner;
-import lexer::{ string_reader, bump, is_eof, nextch, new_string_reader,
+import lexer::{ string_reader, bump, is_eof, nextch,
                is_whitespace, get_str_from, string_reader_as_reader };
 
 export cmnt;
@@ -176,8 +176,9 @@ fn gather_comments_and_literals(span_diagnostic: diagnostic::span_handler,
         {|x|str::hash(*x)},
         {|x,y|str::eq(*x, *y)}
     );
-    let rdr = new_string_reader(span_diagnostic,
-                                codemap::new_filemap(path, src, 0u, 0u), itr);
+    let rdr = lexer::new_low_level_string_reader
+        (span_diagnostic, codemap::new_filemap(path, src, 0u, 0u), itr);
+
     let mut comments: [cmnt] = [];
     let mut literals: [lit] = [];
     let mut first_read: bool = true;
@@ -195,14 +196,17 @@ fn gather_comments_and_literals(span_diagnostic: diagnostic::span_handler,
             }
             break;
         }
-        let bpos = rdr.pos;
-        let tok = rdr.next_token();
-        if token::is_lit(tok.tok) {
-            let s = get_str_from(rdr, bpos);
-            literals += [{lit: s, pos: tok.chpos}];
+
+
+        let bstart = rdr.pos;
+        //discard, and look ahead; we're working with internal state
+        let {tok: tok, sp: sp} = rdr.next_token();
+        if token::is_lit(tok) {
+            let s = get_str_from(rdr, bstart);
+            literals += [{lit: s, pos: sp.lo}];
             log(debug, "tok lit: " + s);
         } else {
-            log(debug, "tok: " + token::to_str(*rdr.interner, tok.tok));
+            log(debug, "tok: " + token::to_str(*rdr.interner, tok));
         }
         first_read = false;
     }
diff --git a/src/libsyntax/parse/eval.rs b/src/libsyntax/parse/eval.rs
index 5ca9b22524b..5ef8417ec6f 100644
--- a/src/libsyntax/parse/eval.rs
+++ b/src/libsyntax/parse/eval.rs
@@ -68,7 +68,7 @@ fn parse_companion_mod(cx: ctx, prefix: str, suffix: option<str>)
                                                 modpath, SOURCE_FILE);
         let inner_attrs = p0.parse_inner_attrs_and_next();
         let m0 = p0.parse_mod_items(token::EOF, inner_attrs.next);
-        cx.sess.chpos = p0.reader.chpos();
+        cx.sess.chpos = r0.chpos;
         cx.sess.byte_pos = cx.sess.byte_pos + r0.pos;
         ret (m0.view_items, m0.items, inner_attrs.inner);
     } else {
@@ -106,7 +106,7 @@ fn eval_crate_directive(cx: ctx, cdir: @ast::crate_directive, prefix: str,
                            /* FIXME: bad */ copy id,
                            ast::item_mod(m0), ast::public, mod_attrs);
         // Thread defids, chpos and byte_pos through the parsers
-        cx.sess.chpos = p0.reader.chpos();
+        cx.sess.chpos = r0.chpos;
         cx.sess.byte_pos = cx.sess.byte_pos + r0.pos;
         items += [i];
       }
diff --git a/src/libsyntax/parse/lexer.rs b/src/libsyntax/parse/lexer.rs
index 8849da5d270..14cb8b41473 100644
--- a/src/libsyntax/parse/lexer.rs
+++ b/src/libsyntax/parse/lexer.rs
@@ -2,17 +2,17 @@ import util::interner;
 import util::interner::intern;
 import diagnostic;
 import ast::{tt_delim,tt_flat};
+import codemap::span;
 
 export reader, string_reader, new_string_reader, is_whitespace;
 export tt_reader,  new_tt_reader, dup_tt_reader;
-export nextch, is_eof, bump, get_str_from;
+export nextch, is_eof, bump, get_str_from, new_low_level_string_reader;
 export string_reader_as_reader, tt_reader_as_reader;
 
 iface reader {
     fn is_eof() -> bool;
-    fn next_token() -> {tok: token::token, chpos: uint};
+    fn next_token() -> {tok: token::token, sp: span};
     fn fatal(str) -> !;
-    fn chpos() -> uint;
     fn interner() -> @interner::interner<@str>;
 }
 
@@ -33,7 +33,7 @@ type tt_reader = ~{
     mut cur: tt_frame,
     /* cached: */
     mut cur_tok: token::token,
-    mut cur_chpos: uint
+    mut cur_span: span
 };
 
 fn new_tt_reader(span_diagnostic: diagnostic::span_handler,
@@ -42,10 +42,11 @@ fn new_tt_reader(span_diagnostic: diagnostic::span_handler,
     let r = ~{span_diagnostic: span_diagnostic, interner: itr,
               mut cur: @{readme: src, mut idx: 0u,
                          up: tt_frame_up(option::none)},
-              mut cur_tok: token::EOF, /* dummy value, never read */
-              mut cur_chpos: 0u /* dummy value, never read */
+              /* dummy values, never read: */
+              mut cur_tok: token::EOF,
+              mut cur_span: ast_util::mk_sp(0u,0u)
              };
-    tt_next_token(r); /* get cur_tok and cur_chpos set up */
+    tt_next_token(r); /* get cur_tok and cur_span set up */
     ret r;
 }
 
@@ -63,7 +64,7 @@ pure fn dup_tt_frame(&&f: tt_frame) -> tt_frame {
 pure fn dup_tt_reader(&&r: tt_reader) -> tt_reader {
     ~{span_diagnostic: r.span_diagnostic, interner: r.interner,
       mut cur: dup_tt_frame(r.cur),
-      mut cur_tok: r.cur_tok, mut cur_chpos: r.cur_chpos}
+      mut cur_tok: r.cur_tok, mut cur_span: r.cur_span}
 }
 
 type string_reader = @{
@@ -80,6 +81,15 @@ type string_reader = @{
 fn new_string_reader(span_diagnostic: diagnostic::span_handler,
                      filemap: codemap::filemap,
                      itr: @interner::interner<@str>) -> string_reader {
+    let r = new_low_level_string_reader(span_diagnostic, filemap, itr);
+    ret r;
+}
+
+/* For comments.rs, which hackily pokes into 'pos' and 'curr' */
+fn new_low_level_string_reader(span_diagnostic: diagnostic::span_handler,
+                               filemap: codemap::filemap,
+                               itr: @interner::interner<@str>)
+    -> string_reader {
     let r = @{span_diagnostic: span_diagnostic, src: filemap.src,
               mut col: 0u, mut pos: 0u, mut curr: -1 as char,
               mut chpos: filemap.start_pos.ch,
@@ -94,7 +104,7 @@ fn new_string_reader(span_diagnostic: diagnostic::span_handler,
 
 impl string_reader_as_reader of reader for string_reader {
     fn is_eof() -> bool { is_eof(self) }
-    fn next_token() -> {tok: token::token, chpos: uint} {
+    fn next_token() -> {tok: token::token, sp: span} {
         consume_whitespace_and_comments(self);
         let start_chpos = self.chpos;
         let tok = if is_eof(self) {
@@ -102,19 +112,18 @@ impl string_reader_as_reader of reader for string_reader {
         } else {
             next_token_inner(self)
         };
-        ret {tok: tok, chpos: start_chpos};
+        ret {tok: tok, sp: ast_util::mk_sp(start_chpos, self.chpos)};
     }
     fn fatal(m: str) -> ! {
         self.span_diagnostic.span_fatal(
             ast_util::mk_sp(self.chpos, self.chpos), m)
     }
-    fn chpos() -> uint { self.chpos }
     fn interner() -> @interner::interner<@str> { self.interner }
 }
 
 impl tt_reader_as_reader of reader for tt_reader {
     fn is_eof() -> bool { self.cur_tok == token::EOF }
-    fn next_token() -> {tok: token::token, chpos: uint} {
+    fn next_token() -> {tok: token::token, sp: span} {
         /* weird resolve bug: if the following `if`, or any of its
         statements are removed, we get resolution errors */
         if false {
@@ -124,15 +133,19 @@ impl tt_reader_as_reader of reader for tt_reader {
         tt_next_token(self)
     }
     fn fatal(m: str) -> ! {
-        self.span_diagnostic.span_fatal(
-            ast_util::mk_sp(self.chpos(), self.chpos()), m);
+        self.span_diagnostic.span_fatal(copy self.cur_span, m);
     }
-    fn chpos() -> uint { self.cur_chpos }
     fn interner() -> @interner::interner<@str> { self.interner }
 }
 
-fn tt_next_token(&&r: tt_reader) -> {tok: token::token, chpos: uint} {
-    let ret_val = { tok: r.cur_tok, chpos: r.cur_chpos };
+fn string_advance_token(&&r: string_reader) {
+    consume_whitespace_and_comments(r);
+
+    next_token_inner(r);
+}
+
+fn tt_next_token(&&r: tt_reader) -> {tok: token::token, sp: span} {
+    let ret_val = { tok: r.cur_tok, sp: r.cur_span };
     if r.cur.idx >= vec::len(r.cur.readme) {
         /* done with this set; pop */
         alt r.cur.up {
@@ -158,8 +171,8 @@ fn tt_next_token(&&r: tt_reader) -> {tok: token::token, chpos: uint} {
             r.cur = @{readme: tts, mut idx: 0u,
                       up: tt_frame_up(option::some(copy r.cur)) };
           }
-          tt_flat(chpos, tok) {
-            r.cur_chpos = chpos; r.cur_tok = tok;
+          tt_flat(sp, tok) {
+            r.cur_span = sp; r.cur_tok = tok;
             r.cur.idx += 1u;
             ret ret_val;
           }
diff --git a/src/libsyntax/parse/parser.rs b/src/libsyntax/parse/parser.rs
index f2481e4adda..08eaa779291 100644
--- a/src/libsyntax/parse/parser.rs
+++ b/src/libsyntax/parse/parser.rs
@@ -63,7 +63,7 @@ class parser {
     let mut token: token::token;
     let mut span: span;
     let mut last_span: span;
-    let mut buffer: [mut {tok: token::token, span: span}]/4;
+    let mut buffer: [mut {tok: token::token, sp: span}]/4;
     let mut buffer_start: int;
     let mut buffer_end: int;
     let mut restriction: restriction;
@@ -75,7 +75,7 @@ class parser {
     {
         self.reader <- rdr;
         let tok0 = self.reader.next_token();
-        let span0 = ast_util::mk_sp(tok0.chpos, self.reader.chpos());
+        let span0 = tok0.sp;
         self.sess = sess;
         self.cfg = cfg;
         self.file_type = ftype;
@@ -83,10 +83,10 @@ class parser {
         self.span = span0;
         self.last_span = span0;
         self.buffer = [mut
-            {tok: tok0.tok, span: span0},
-            {tok: tok0.tok, span: span0},
-            {tok: tok0.tok, span: span0},
-            {tok: tok0.tok, span: span0}
+            {tok: tok0.tok, sp: span0},
+            {tok: tok0.tok, sp: span0},
+            {tok: tok0.tok, sp: span0},
+            {tok: tok0.tok, sp: span0}
         ]/4;
         self.buffer_start = 0;
         self.buffer_end = 0;
@@ -100,16 +100,15 @@ class parser {
 
     fn bump() {
         self.last_span = self.span;
-        if self.buffer_start == self.buffer_end {
-            let next = self.reader.next_token();
-            self.token = next.tok;
-            self.span = mk_sp(next.chpos, self.reader.chpos());
+        let next = if self.buffer_start == self.buffer_end {
+            self.reader.next_token()
         } else {
             let next = self.buffer[self.buffer_start];
             self.buffer_start = (self.buffer_start + 1) & 3;
-            self.token = next.tok;
-            self.span = next.span;
-        }
+            next
+        };
+        self.token = next.tok;
+        self.span = next.sp;
     }
     fn swap(next: token::token, lo: uint, hi: uint) {
         self.token = next;
@@ -124,9 +123,7 @@ class parser {
     fn look_ahead(distance: uint) -> token::token {
         let dist = distance as int;
         while self.buffer_length() < dist {
-            let next = self.reader.next_token();
-            let sp = mk_sp(next.chpos, self.reader.chpos());
-            self.buffer[self.buffer_end] = {tok: next.tok, span: sp};
+            self.buffer[self.buffer_end] = self.reader.next_token();
             self.buffer_end = (self.buffer_end + 1) & 3;
         }
         ret copy self.buffer[(self.buffer_start + dist - 1) & 3].tok;
@@ -1082,7 +1079,7 @@ class parser {
               }
               _ { /* ok */ }
             }
-            let res = tt_flat(p.span.lo, p.token);
+            let res = tt_flat(p.span, p.token);
             p.bump();
             ret res;
         }