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;
 

src/algorithms/randomness/rand-range.md

@@ -4,9 +4,7 @@
 
 Generates a random value within half-open `[0, 10)` range (not including `10`) with [`Rng::gen_range`].
 
-```rust,ignore
-extern crate rand;
-
+```rust,edition2018,ignore
 use rand::Rng;
 
 fn main() {
@@ -20,9 +18,7 @@ fn main() {
 This has the same effect, but may be faster when repeatedly generating numbers
 in the same range.
 
-```rust,ignore
-extern crate rand;
-
+```rust,edition2018,ignore
 
 use rand::distributions::{Distribution, Uniform};
 

src/algorithms/randomness/rand.md

@@ -8,9 +8,7 @@ initialized generator. Integers are uniformly distributed over the range of the
 type, and floating point numbers are uniformly distributed from 0 up to but not
 including 1.
 
-```rust
-extern crate rand;
-
+```rust,edition2018
 use rand::Rng;
 
 fn main() {

src/algorithms/sorting/sort.md

@@ -6,7 +6,7 @@ This example sorts a Vector of integers via [`vec::sort`]. Alternative would
 be to use [`vec::sort_unstable`] which can be faster, but does not preserve
 the order of equal elements.
 
-```rust
+```rust,edition2018
 fn main() {
     let mut vec = vec![1, 5, 10, 2, 15];
     

src/algorithms/sorting/sort_float.md

@@ -4,7 +4,7 @@
 
 A Vector of f32 or f64 can be sorted with [`vec::sort_by`] and [`PartialOrd::partial_cmp`].
 
-```rust
+```rust,edition2018
 fn main() {
     let mut vec = vec![1.1, 1.15, 5.5, 1.123, 2.0];
 

src/algorithms/sorting/sort_struct.md

@@ -7,7 +7,7 @@ order (By name and age). In order to make Person sortable you need four traits [
 [`PartialEq`], [`Ord`] and [`PartialOrd`]. These traits can be simply derived.
 You can also provide a custom comparator function using a [`vec:sort_by`] method and sort only by age.
 
-```rust
+```rust,edition2018
 #[derive(Debug, Eq, Ord, PartialEq, PartialOrd)]
 struct Person {
     name: String,

src/cli/ansi_terminal/ansi_term-basic.md

@@ -10,9 +10,7 @@ There are two main data structures in [`ansi_term`]: [`ANSIString`] and [`Style`
 
 ### Printing colored text to the Terminal
 
-```rust
-extern crate ansi_term;
-
+```rust,edition2018
 use ansi_term::Colour;
 
 fn main() {
@@ -29,9 +27,7 @@ For anything more complex than plain foreground colour changes, the code
 needs to construct `Style` struct. [`Style::new()`] creates the struct,
 and properties chained.
 
-```rust
-extern crate ansi_term;
-
+```rust,edition2018
 use ansi_term::Style;
 
 fn main() {
@@ -43,9 +39,7 @@ fn main() {
 
 `Colour` implements many similar functions as `Style` and can chain methods.
 
-```rust
-extern crate ansi_term;
-
+```rust,edition2018
 use ansi_term::Colour;
 use ansi_term::Style;
 

src/cli/arguments/clap-basic.md

@@ -11,9 +11,7 @@ use to retrieve the value passed. The `short` and `long` options control the
 flag the user will be expected to type; short flags look like `-f` and long
 flags look like `--file`.
 
-```rust
-extern crate clap;
-
+```rust,edition2018
 use clap::{Arg, App};
 
 fn main() {

src/compression/tar/tar-compress.md

@@ -10,9 +10,7 @@ under `backup/logs`path with [`Builder::append_dir_all`].
 [`GzEncoder`] is responsible for transparently compressing the
 data prior to writing it into `archive.tar.gz`.
 
-```rust,no_run
-extern crate tar;
-extern crate flate2;
+```rust,edition2018,no_run
 
 use std::fs::File;
 use flate2::Compression;

src/compression/tar/tar-decompress.md

@@ -7,9 +7,7 @@ extract ([`Archive::unpack`]) all files from a compressed tarball
 named `archive.tar.gz` located in the current working directory
 to the same location.
 
-```rust,no_run
-extern crate flate2;
-extern crate tar;
+```rust,edition2018,no_run
 
 use std::fs::File;
 use flate2::read::GzDecoder;

src/compression/tar/tar-strip-prefix.md

@@ -6,12 +6,8 @@ Iterate over the [`Archive::entries`].  Use [`Path::strip_prefix`] to remove
 the specified path prefix (`bundle/logs`).  Finally, extract the [`tar::Entry`]
 via [`Entry::unpack`].
 
-```rust,no_run
-# #[macro_use]
-# extern crate error_chain;
-extern crate flate2;
-extern crate tar;
-
+```rust,edition2018,no_run
+# use error_chain::error_chain;
 use std::fs::File;
 use std::path::PathBuf;
 use flate2::read::GzDecoder;

src/concurrency/parallel/rayon-any-all.md

@@ -4,9 +4,7 @@
 
 This example demonstrates using the [`rayon::any`] and [`rayon::all`] methods, which are parallelized counterparts to [`std::any`] and [`std::all`]. [`rayon::any`] checks in parallel whether any element of the iterator matches the predicate, and returns as soon as one is found. [`rayon::all`] checks in parallel whether all elements of the iterator match the predicate, and returns as soon as a non-matching element is found.
 
-```rust
-extern crate rayon;
-
+```rust,edition2018
 use rayon::prelude::*;
 
 fn main() {

src/concurrency/parallel/rayon-iter-mut.md

@@ -6,9 +6,7 @@ The example uses the `rayon` crate, which is a data parallelism library for Rust
 `rayon` provides the [`par_iter_mut`] method for any parallel iterable data type.
 This is an iterator-like chain that potentially executes in parallel.
 
-```rust
-extern crate rayon;
-
+```rust,edition2018
 use rayon::prelude::*;
 
 fn main() {

src/concurrency/parallel/rayon-map-reduce.md

@@ -11,9 +11,7 @@ new iteration, and [`rayon::reduce`] performs an operation given the previous
 reduction and the current element.  Also shows use of [`rayon::sum`],
 which has the same result as the reduce operation in this example.
 
-```rust
-extern crate rayon;
-
+```rust,edition2018
 use rayon::prelude::*;
 
 struct Person {

src/concurrency/parallel/rayon-parallel-search.md

@@ -12,9 +12,7 @@ necessarily the first one.
 Also note that the argument to the closure is a reference to a reference
 (`&&x`). See the discussion on [`std::find`] for additional details.
 
-```rust
-extern crate rayon;
-
+```rust,edition2018
 use rayon::prelude::*;
 
 fn main() {

src/concurrency/parallel/rayon-parallel-sort.md

@@ -9,9 +9,7 @@ values in parallel.  Although [multiple options]
 exist to sort an enumerable data type, [`par_sort_unstable`]
 is usually faster than [stable sorting] algorithms.
 
-```rust,ignore
-extern crate rand;
-extern crate rayon;
+```rust,edition2018,ignore
 
 use rand::{Rng, thread_rng};
 use rand::distributions::Alphanumeric;

src/concurrency/parallel/rayon-thumbnails.md

@@ -8,12 +8,8 @@ then saves them in a new folder called `thumbnails`.
 [`glob::glob_with`] finds jpeg files in current directory. `rayon` resizes
 images in parallel using [`par_iter`] calling  [`DynamicImage::resize`].
 
-```rust,no_run
-# #[macro_use]
-# extern crate error_chain;
-extern crate glob;
-extern crate image;
-extern crate rayon;
+```rust,edition2018,no_run
+# use error_chain::error_chain;
 
 use std::path::Path;
 use std::fs::create_dir_all;
@@ -38,7 +34,7 @@ fn main() -> Result<()> {
         .collect();
 
     if files.len() == 0 {
-        bail!("No .jpg files found in current directory");
+        error_chain::bail!("No .jpg files found in current directory");
     }
 
     let thumb_dir = "thumbnails";

src/concurrency/thread/crossbeam-spawn.md

@@ -9,9 +9,7 @@ you can reference data from the calling function.
 
 This example splits the array in half and performs the work in separate threads.
 
-```rust
-extern crate crossbeam;
-
+```rust,edition2018
 fn main() {
     let arr = &[1, 25, -4, 10];
     let max = find_max(arr);

src/concurrency/thread/crossbeam-spsc.md

@@ -9,9 +9,7 @@ exchanged between the two threads using a [`crossbeam_channel::unbounded`]
 channel, meaning there is no limit to the number of storeable messages. The
 producer thread sleeps for half a second in between messages.
 
-```rust
-extern crate crossbeam;
-extern crate crossbeam_channel;
+```rust,edition2018
 
 use std::{thread, time};
 use crossbeam_channel::unbounded;