Changed the lexer to accept #! comments on the first line.

Author: Margaret Meyerhofer

src/librustsyntax/codemap.rs

@@ -12,6 +12,7 @@ export new_filemap;
 export new_filemap_w_substr;
 export mk_substr_filename;
 export lookup_char_pos;
+export lookup_char_pos_adj;
 export adjust_span;
 export span_to_str;
 export span_to_filename;

src/librustsyntax/parse/lexer.rs

@@ -119,6 +119,17 @@ fn consume_any_line_comment(rdr: reader) {
           '*' { rdr.bump(); rdr.bump(); ret consume_block_comment(rdr); }
           _ { ret; }
         }
+    } else if rdr.curr == '#' {
+        if rdr.next() == '!' {
+            let cmap = codemap::new_codemap();
+            (*cmap).files.push(rdr.filemap);
+            let mut loc = codemap::lookup_char_pos_adj(cmap, rdr.chpos);
+            if loc.line == 1u && loc.col == 0u {
+                while rdr.curr != '\n' && !rdr.is_eof() { rdr.bump(); }
+                loc = codemap::lookup_char_pos_adj(cmap, rdr.chpos);
+                ret consume_whitespace_and_comments(rdr);
+            }
+        }
     }
 }