auto merge of #11416 : bjz/rust/remove-print-fns, r=alexcrichton

The `print!` and `println!` macros are now the preferred method of printing, and so there is no reason to export the `stdio` functions in the prelude. The functions have also been replaced by their macro counterparts in the tutorial and other documentation so that newcomers don't get confused about what they should be using.

Author: bors

doc/guide-conditions.md

@@ -275,7 +275,7 @@ fn main() {
 
     };
     if result.is_err() {
-            println("parsing failed");
+            println!("parsing failed");
     }
 }
 

doc/guide-container.md

@@ -218,12 +218,12 @@ let xs = [2u, 3, 5, 7, 11, 13, 17];
 
 // print out all the elements in the vector
 for x in xs.iter() {
-    println(x.to_str())
+    println!("{}", *x)
 }
 
 // print out all but the first 3 elements in the vector
 for x in xs.iter().skip(3) {
-    println(x.to_str())
+    println!("{}", *x)
 }
 ~~~
 

doc/guide-pointers.md

@@ -222,7 +222,7 @@ struct Point {
 fn main() {
     let a = Point { x: 10, y: 20 };
     do spawn {
-        println(a.x.to_str());
+        println!("{}", a.x);
     }
 }
 ~~~
@@ -239,7 +239,7 @@ struct Point {
 fn main() {
     let a = ~Point { x: 10, y: 20 };
     do spawn {
-        println(a.x.to_str());
+        println!("{}", a.x);
     }
 }
 ~~~
@@ -270,18 +270,22 @@ struct Point {
 fn main() {
     let a = ~Point { x: 10, y: 20 };
     let b = a;
-    println(b.x.to_str());
-    println(a.x.to_str());
+    println!("{}", b.x);
+    println!("{}", a.x);
 }
 ~~~
 
 You'll get this error:
 
 ~~~ {.notrust}
-test.rs:10:12: 10:13 error: use of moved value: `a`
-test.rs:10     println(a.x.to_str());
-                       ^
-test.rs:8:8: 8:9 note: `a` moved here because it has type `~Point`, which is moved by default (use `ref` to override)
+test.rs:10:20: 10:21 error: use of moved value: `a`
+test.rs:10     println!("{}", a.x);
+                              ^
+note: in expansion of format_args!
+<std-macros>:158:27: 158:81 note: expansion site
+<std-macros>:157:5: 159:6 note: in expansion of println!
+test.rs:10:5: 10:25 note: expansion site
+test.rs:8:9: 8:10 note: `a` moved here because it has type `~Point`, which is moved by default (use `ref` to override)
 test.rs:8     let b = a;
                   ^
 ~~~
@@ -297,8 +301,8 @@ struct Point {
 fn main() {
     let a = @Point { x: 10, y: 20 };
     let b = a;
-    println(b.x.to_str());
-    println(a.x.to_str());
+    println!("{}", b.x);
+    println!("{}", a.x);
 }
 ~~~
 
@@ -367,7 +371,7 @@ compile?
 
 ~~~rust{.xfail-test}
 fn main() {
-    println(x.to_str());
+    println!("{}", x);
     let x = 5;
 }
 ~~~

doc/guide-rustpkg.md

@@ -143,7 +143,7 @@ Next, let's add a source file:
 #[license = "MIT"];
 
 pub fn world() {
-    println("Hello, world.");
+    println!("Hello, world.");
 }
 ~~~
 

doc/guide-tasks.md

@@ -72,15 +72,15 @@ closure in the new task.
 # use std::task::spawn;
 
 // Print something profound in a different task using a named function
-fn print_message() { println("I am running in a different task!"); }
+fn print_message() { println!("I am running in a different task!"); }
 spawn(print_message);
 
 // Print something more profound in a different task using a lambda expression
-spawn(proc() println("I am also running in a different task!") );
+spawn(proc() println!("I am also running in a different task!") );
 
 // The canonical way to spawn is using `do` notation
 do spawn {
-    println("I too am running in a different task!");
+    println!("I too am running in a different task!");
 }
 ~~~~
 

doc/rust.md

@@ -2668,7 +2668,7 @@ An example:
 let mut i = 0;
 
 while i < 10 {
-    println("hello\n");
+    println!("hello");
     i = i + 1;
 }
 ~~~~
@@ -3267,7 +3267,7 @@ impl Printable for int {
 }
 
 fn print(a: @Printable) {
-   println(a.to_string());
+   println!("{}", a.to_string());
 }
 
 fn main() {