---

yaml
---
r: 63095
b: refs/heads/snap-stage3
c: 239b81f
h: refs/heads/master
i:
  63093: 85e6916
  63091: 398f102
  63087: 5a0f3fb
v: v3

Author: catamorphism

[refs]

@@ -1,7 +1,7 @@
 ---
 refs/heads/master: 2d28d645422c1617be58c8ca7ad9a457264ca850
 refs/heads/snap-stage1: e33de59e47c5076a89eadeb38f4934f58a3618a6
-refs/heads/snap-stage3: 83b68a2f69471e0217422cf30d6c45ec4fe28b70
+refs/heads/snap-stage3: 239b81f111d522b1fbb0dbefdde16715ef68a204
 refs/heads/try: 7b78b52e602bb3ea8174f9b2006bff3315f03ef9
 refs/tags/release-0.1: 1f5c5126e96c79d22cb7862f75304136e204f105
 refs/heads/ndm: f3868061cd7988080c30d6d5bf352a5a5fe2460b

branches/snap-stage3/doc/tutorial.md

@@ -569,10 +569,8 @@ loop {
 This code prints out a weird sequence of numbers and stops as soon as
 it finds one that can be divided by five.
 
-Rust also has a `for` construct. It's different from C's `for` and it works
-best when iterating over collections. See the section on [closures](#closures)
-to find out how to use `for` and higher-order functions for enumerating
-elements of a collection.
+For more involved iteration, such as enumerating the elements of a
+collection, Rust uses [higher-order functions](#closures).
 
 # Data structures
 
@@ -1395,7 +1393,6 @@ assert!(crayons.len() == 3);
 assert!(!crayons.is_empty());
 
 // Iterate over a vector, obtaining a pointer to each element
-// (`for` is explained in the next section)
 for crayons.each |crayon| {
     let delicious_crayon_wax = unwrap_crayon(*crayon);
     eat_crayon_wax(delicious_crayon_wax);

branches/snap-stage3/src/libstd/str.rs

@@ -39,6 +39,13 @@ use vec::{OwnedVector, OwnedCopyableVector};
 
 #[cfg(not(test))] use cmp::{Eq, Ord, Equiv, TotalEq};
 
+/*
+Section: Conditions
+*/
+condition! {
+    not_utf8: (~str) -> ~str;
+}
+
 /*
 Section: Creating a string
 */
@@ -48,11 +55,20 @@ Section: Creating a string
  *
  * # Failure
  *
- * Fails if invalid UTF-8
+ * Raises the `not_utf8` condition if invalid UTF-8
  */
-pub fn from_bytes(vv: &const [u8]) -> ~str {
-    assert!(is_utf8(vv));
-    return unsafe { raw::from_bytes(vv) };
+
+pub fn from_bytes(vv: &[u8]) -> ~str {
+    use str::not_utf8::cond;
+
+    if !is_utf8(vv) {
+        let first_bad_byte = vec::find(vv, |b| !is_utf8([*b])).get();
+        cond.raise(fmt!("from_bytes: input is not UTF-8; first bad byte is %u",
+                        first_bad_byte as uint))
+    }
+    else {
+        return unsafe { raw::from_bytes(vv) }
+    }
 }
 
 /**
@@ -3563,9 +3579,10 @@ mod tests {
     }
 
     #[test]
-    #[should_fail]
     #[ignore(cfg(windows))]
     fn test_from_bytes_fail() {
+        use str::not_utf8::cond;
+
         let bb = ~[0xff_u8, 0xb8_u8, 0xa8_u8,
                   0xe0_u8, 0xb9_u8, 0x84_u8,
                   0xe0_u8, 0xb8_u8, 0x97_u8,
@@ -3577,7 +3594,15 @@ mod tests {
                   0x20_u8, 0x4e_u8, 0x61_u8,
                   0x6d_u8];
 
-         let _x = from_bytes(bb);
+        let mut error_happened = false;
+        let _x = do cond.trap(|err| {
+            assert_eq!(err, ~"from_bytes: input is not UTF-8; first bad byte is 255");
+            error_happened = true;
+            ~""
+        }).in {
+            from_bytes(bb)
+        };
+        assert!(error_happened);
     }
 
     #[test]