Update to edition 2018 (#565)

* Update to edition 2018

Update mdbook to 0.3.5

Command:
sed -i '/extern crate/ {N;s/\n$//}' src/**.md; sed -i 's/extern crate error_chain;/use error_chain::error_chain;/; s/extern crate lazy_static;/use lazy_static::lazy_static;/; s/extern crate bitflags;/use bitflags::bitflags;/; s/extern crate serde_json;/ use serde_json::json;/; s/extern crate serde_derive;/use serde::{Serialize, Deserialize};/; /macro_use/d; /extern crate/ d; s/```rust/```rust,edition2018/; s/bail!/error_chain::&/; s/\(debug\|info\|warn\|error\)!/log::&/;' src/**.md

Fix #530

* Update rand-dist.md

* Fixes #569

* dump syslog

version 4 depends on error-chain v 0.11 and version 5 depends on v 0.12 
!!!!

Co-authored-by: Andrew Gauger <[email protected]>

Author: pickfire

CONTRIBUTING.md

@@ -20,7 +20,7 @@ cd rust-cookbook
 Cookbook is built with [mdBook], so install that first with Cargo:
 
 ```
-cargo install --version 0.1.8 mdbook
+cargo install --version 0.3.5 mdbook
 ```
 
 To build and view the cookbook locally, run:

Cargo.toml

@@ -2,13 +2,15 @@
 name = "rust-cookbook"
 version = "0.1.0"
 authors = ["Brian Anderson <[email protected]>"]
+edition = "2018"
 license = "MIT/Apache-2.0"
 publish = false
 
 build = "build.rs"
 
 [dependencies]
 ansi_term = "0.11.0"
+approx = "0.3"
 base64 = "0.9"
 bitflags = "1.0"
 byteorder = "1.0"
@@ -58,7 +60,7 @@ url = "2.1"
 walkdir = "2.0"
 
 [target.'cfg(target_os = "linux")'.dependencies]
-syslog = "4.0"
+syslog = "5.0"
 
 [build-dependencies]
 skeptic = "0.13"

README.md

@@ -19,7 +19,7 @@ If you'd like to read it locally:
 ```bash
 $ git clone https://github.com/rust-lang-nursery/rust-cookbook
 $ cd rust-cookbook
-$ cargo install mdbook --vers "0.1.8"
+$ cargo install mdbook --vers "0.3.5"
 $ mdbook serve --open
 ```
 

book.toml

@@ -3,12 +3,14 @@
 title = "Rust Cookbook"
 description = "Collection of useful Rust code examples"
 authors = ["Rust Language Community"]
+edition = "2018"
 multilingual = false
+language = "en"
 src = "src"
 
 [output.html]
 mathjax-support = false
-theme = "theme"
+# theme = "theme"
 additional-css = ["theme/custom.css"]
 
 [output.html.playpen]

ci/install_deps.sh

@@ -18,7 +18,7 @@ if [[ "${CONTENT_TESTS:-}" == 1 ]]; then
         pyenv local 3.6.0
         pip3 install --user link-checker==0.1.0
     fi
-    cargo install mdbook --vers '0.1.8' --debug
+    cargo install mdbook --vers '0.3.5' --debug
 fi
 
 exit 0

src/about.md

@@ -56,8 +56,7 @@ Consider this example for "generate random numbers within a range":
 
 [![rand-badge]][rand] [![cat-science-badge]][cat-science]
 
-```rust
-extern crate rand;
+```rust,edition2018
 use rand::Rng;
 
 fn main() {
@@ -111,10 +110,8 @@ The basic pattern we use is to have a `fn main() -> Result`.
 
 The structure generally looks like:
 
-```rust
-#[macro_use]
-extern crate error_chain;
-
+```rust,edition2018
+use error_chain::error_chain;
 use std::net::IpAddr;
 use std::str;
 
@@ -150,10 +147,8 @@ default like below.  In order to read full contents click on the
 "expand" (<i class="fa fa-expand"></i>) button located in the top
 right corner of the snippet.
 
-```rust
-# #[macro_use]
-# extern crate error_chain;
-extern crate url;
+```rust,edition2018
+# use error_chain::error_chain;
 
 use url::{Url, Position};
 #

src/algorithms/randomness/rand-choose.md

@@ -5,9 +5,7 @@
 Randomly generates a string of given length ASCII characters with custom
 user-defined bytestring, with [`gen_range`].
 
-```rust
-extern crate rand;
-
+```rust,edition2018
 fn main() {
     use rand::Rng;
     const CHARSET: &[u8] = b"ABCDEFGHIJKLMNOPQRSTUVWXYZ\

src/algorithms/randomness/rand-custom.md

@@ -5,9 +5,7 @@
 Randomly generates a tuple `(i32, bool, f64)` and variable of user defined type `Point`.
 Implements the [`Distribution`] trait on type Point for [`Standard`] in order to allow random generation.
 
-```rust,ignore
-extern crate rand;
-
+```rust,edition2018,ignore
 use rand::Rng;
 use rand::distributions::{Distribution, Standard};
 

src/algorithms/randomness/rand-dist.md

@@ -12,10 +12,7 @@ generator [`rand::Rng`].
 The [distributions available are documented here][rand-distributions].
 An example using the [`Normal`] distribution is shown below.
 
-```rust,ignore
-extern crate rand_distr;
-extern crate rand;
-
+```rust,edition2018,ignore
 use rand_distr::{Distribution, Normal, NormalError};
 
 fn main() -> Result<(), NormalError> {

src/algorithms/randomness/rand-passwd.md

@@ -5,9 +5,7 @@
 Randomly generates a string of given length ASCII characters in the range `A-Z,
 a-z, 0-9`, with [`Alphanumeric`] sample.
 
-```rust,ignore
-extern crate rand;
-
+```rust,edition2018,ignore
 use rand::{thread_rng, Rng};
 use rand::distributions::Alphanumeric;