stdlib: Make io failures recoverable by returning a result

2 files changed, 19 insertions, 4 deletions

diff --git a/src/comp/syntax/codemap.rs b/src/comp/syntax/codemap.rs
index 5156570c8ba..2db5e1e2c4c 100644
--- a/src/comp/syntax/codemap.rs
+++ b/src/comp/syntax/codemap.rs
@@ -1,4 +1,4 @@
-import std::{vec, uint, str, term, io, option};
+import std::{vec, uint, str, term, io, option, result};
 import std::option::{some, none};
 
 type filename = str;
@@ -154,7 +154,13 @@ fn maybe_highlight_lines(sp: option::t<span>, cm: codemap,
 
         // FIXME: reading in the entire file is the worst possible way to
         //        get access to the necessary lines.
-        let file = io::read_whole_file_str(lines.name);
+        let file = alt io::read_whole_file_str(lines.name) {
+          result::ok(file) { file }
+          result::err(e) {
+            emit_error(none, e, cm);
+            fail;
+          }
+        };
         let fm = get_filemap(cm, lines.name);
 
         // arbitrarily only print up to six lines of the error
diff --git a/src/comp/syntax/parse/parser.rs b/src/comp/syntax/parse/parser.rs
index dc1b7fb3047..f605a2fb699 100644
--- a/src/comp/syntax/parse/parser.rs
+++ b/src/comp/syntax/parse/parser.rs
@@ -1,5 +1,5 @@
 
-import std::{io, vec, str, option, either};
+import std::{io, vec, str, option, either, result};
 import std::option::{some, none};
 import std::either::{left, right};
 import std::map::{hashmap, new_str_hash};
@@ -53,7 +53,16 @@ type parser =
 fn new_parser_from_file(sess: parse_sess, cfg: ast::crate_cfg, path: str,
                         chpos: uint, byte_pos: uint, ftype: file_type) ->
    parser {
-    let src = io::read_whole_file_str(path);
+    let src = alt io::read_whole_file_str(path) {
+      result::ok(src) {
+        // FIXME: This copy is unfortunate
+        src
+      }
+      result::err(e) {
+        codemap::emit_error(none, e, sess.cm);
+        fail;
+      }
+    };
     let filemap = codemap::new_filemap(path, chpos, byte_pos);
     sess.cm.files += [filemap];
     let itr = @interner::mk(str::hash, str::eq);