Rollup merge of #40332 - steveklabnik:extract-book, r=alexcrichton

Extract book into a submodule

Part of https://github.com/rust-lang/rust/issues/39588

We probably don't want to land this till after the beta branches on friday, but would still ❤️ a review from @alexcrichton , since I am a rustbuild noob.

This pr:

1. removes the book
2. adds it back in as a submodule
3. the submodule includes both the old book and the new book
4. it also includes an index page explaining the difference in editions
5. it also includes redirect pages for the old book URLs.
6. so we build all that stuff too.

r? @alexcrichton

4 files changed, 10 insertions, 10 deletions

diff --git a/src/libcore/char.rs b/src/libcore/char.rs
index 649fdf394e4..19e69ca296d 100644
--- a/src/libcore/char.rs
+++ b/src/libcore/char.rs
@@ -94,7 +94,7 @@ pub const MAX: char = '\u{10ffff}';
 ///
 /// [`char`]: ../../std/primitive.char.html
 /// [`u32`]: ../../std/primitive.u32.html
-/// [`as`]: ../../book/casting-between-types.html#as
+/// [`as`]: ../../book/first-edition/casting-between-types.html#as
 ///
 /// For an unsafe version of this function which ignores these checks, see
 /// [`from_u32_unchecked`].
@@ -146,7 +146,7 @@ pub fn from_u32(i: u32) -> Option<char> {
 ///
 /// [`char`]: ../../std/primitive.char.html
 /// [`u32`]: ../../std/primitive.u32.html
-/// [`as`]: ../../book/casting-between-types.html#as
+/// [`as`]: ../../book/first-edition/casting-between-types.html#as
 ///
 /// # Safety
 ///
diff --git a/src/libcore/iter/iterator.rs b/src/libcore/iter/iterator.rs
index 1301c311c14..fb98e43aa61 100644
--- a/src/libcore/iter/iterator.rs
+++ b/src/libcore/iter/iterator.rs
@@ -409,7 +409,7 @@ pub trait Iterator {
     /// If you're doing some sort of looping for a side effect, it's considered
     /// more idiomatic to use [`for`] than `map()`.
     ///
-    /// [`for`]: ../../book/loops.html#for
+    /// [`for`]: ../../book/first-edition/loops.html#for
     ///
     /// # Examples
     ///
@@ -1306,7 +1306,7 @@ pub trait Iterator {
     /// use a `for` loop with a list of things to build up a result. Those
     /// can be turned into `fold()`s:
     ///
-    /// [`for`]: ../../book/loops.html#for
+    /// [`for`]: ../../book/first-edition/loops.html#for
     ///
     /// ```
     /// let numbers = [1, 2, 3, 4, 5];
diff --git a/src/libcore/mem.rs b/src/libcore/mem.rs
index ba65e4494a8..f5cf3724d07 100644
--- a/src/libcore/mem.rs
+++ b/src/libcore/mem.rs
@@ -164,7 +164,7 @@ pub use intrinsics::transmute;
 /// [uninit]: fn.uninitialized.html
 /// [clone]: ../clone/trait.Clone.html
 /// [swap]: fn.swap.html
-/// [FFI]: ../../book/ffi.html
+/// [FFI]: ../../book/first-edition/ffi.html
 /// [box]: ../../std/boxed/struct.Box.html
 /// [into_raw]: ../../std/boxed/struct.Box.html#method.into_raw
 /// [ub]: ../../reference/behavior-considered-undefined.html
@@ -199,7 +199,7 @@ pub fn size_of<T>() -> usize {
 /// then `size_of_val` can be used to get the dynamically-known size.
 ///
 /// [slice]: ../../std/primitive.slice.html
-/// [trait object]: ../../book/trait-objects.html
+/// [trait object]: ../../book/first-edition/trait-objects.html
 ///
 /// # Examples
 ///
@@ -317,7 +317,7 @@ pub fn align_of_val<T: ?Sized>(val: &T) -> usize {
 /// many of the same caveats.
 ///
 /// [uninit]: fn.uninitialized.html
-/// [FFI]: ../../book/ffi.html
+/// [FFI]: ../../book/first-edition/ffi.html
 /// [ub]: ../../reference/behavior-considered-undefined.html
 ///
 /// # Examples
@@ -343,7 +343,7 @@ pub unsafe fn zeroed<T>() -> T {
 /// This is useful for [FFI] functions and initializing arrays sometimes,
 /// but should generally be avoided.
 ///
-/// [FFI]: ../../book/ffi.html
+/// [FFI]: ../../book/first-edition/ffi.html
 ///
 /// # Undefined behavior
 ///
@@ -525,7 +525,7 @@ pub fn replace<T>(dest: &mut T, mut src: T) -> T {
 /// it will not release any borrows, as borrows are based on lexical scope.
 ///
 /// This effectively does nothing for
-/// [types which implement `Copy`](../../book/ownership.html#copy-types),
+/// [types which implement `Copy`](../../book/first-edition/ownership.html#copy-types),
 /// e.g. integers. Such values are copied and _then_ moved into the function,
 /// so the value persists after this function call.
 ///
diff --git a/src/libcore/raw.rs b/src/libcore/raw.rs
index a7d0d3899b1..a95f05227fb 100644
--- a/src/libcore/raw.rs
+++ b/src/libcore/raw.rs
@@ -25,7 +25,7 @@
 /// Book][moreinfo] contains more details about the precise nature of
 /// these internals.
 ///
-/// [moreinfo]: ../../book/trait-objects.html#representation
+/// [moreinfo]: ../../book/first-edition/trait-objects.html#representation
 ///
 /// `TraitObject` is guaranteed to match layouts, but it is not the
 /// type of trait objects (e.g. the fields are not directly accessible