Add edition to Cargo.toml, use 2018 edition idoms

Ran "cargo fix --edition-idioms"

Cargo.toml

@@ -3,6 +3,7 @@ name = "rust-book"
 version = "0.0.1"
 authors = ["Steve Klabnik <steve@steveklabnik.com>"]
 description = "The Rust Book"
+edition = "2018"
 
 [[bin]]
 name = "concat_chapters"

tools/src/bin/concat_chapters.rs

@@ -9,7 +9,7 @@
 // except according to those terms.
 
 #[macro_use] extern crate lazy_static;
-extern crate regex;
+
 
 use std::env;
 use std::io;

tools/src/bin/convert_quotes.rs

@@ -34,7 +34,7 @@ fn main() {
             is_in_html_tag = false;
             write!(io::stdout(), "{}\n", line).unwrap();
         } else {
-            let mut modified_line = &mut String::new();
+            let modified_line = &mut String::new();
             let mut previous_char = std::char::REPLACEMENT_CHARACTER;
             let mut chars_in_line = line.chars();
 

tools/src/bin/lfp.rs

@@ -11,10 +11,10 @@
 // We have some long regex literals, so:
 // ignore-tidy-linelength
 
-extern crate rustc_serialize;
-extern crate docopt;
+
+
 use docopt::Docopt;
-extern crate walkdir;
+use walkdir;
 use std::{path, fs, io};
 use std::io::{BufRead, Write};
 

tools/src/bin/link2print.rs

@@ -12,7 +12,7 @@
 // FIXME: We have some long lines that could be refactored, but it's not a big deal.
 // ignore-tidy-linelength
 
-extern crate regex;
+
 
 use std::collections::HashMap;
 use std::io;
@@ -40,7 +40,7 @@ fn parse_references(buffer: String) -> (String, HashMap<String, String>) {
     let mut ref_map = HashMap::new();
     // FIXME: Currently doesn't handle "title" in following line
     let re = Regex::new(r###"(?m)\n?^ {0,3}\[([^]]+)\]:[[:blank:]]*(.*)$"###).unwrap();
-    let output = re.replace_all(&buffer, |caps: &Captures| {
+    let output = re.replace_all(&buffer, |caps: &Captures<'_>| {
         let key = caps.at(1).unwrap().to_owned().to_uppercase();
         let val = caps.at(2).unwrap().to_owned();
         if ref_map.insert(key, val).is_some() {
@@ -55,7 +55,7 @@ fn parse_links((buffer, ref_map): (String, HashMap<String, String>)) -> String {
     // FIXME: check which punctuation is allowed by spec
     let re = Regex::new(r###"(?:(?P<pre>(?:```(?:[^`]|`[^`])*`?\n```\n)|(?:[^[]`[^`\n]+[\n]?[^`\n]*`))|(?:\[(?P<name>[^]]+)\](?:(?:\([[:blank:]]*(?P<val>[^")]*[^ ])(?:[[:blank:]]*"[^"]*")?\))|(?:\[(?P<key>[^]]*)\]))?))"###).expect("could not create regex");
     let error_code = Regex::new(r###"^E\d{4}$"###).expect("could not create regex");
-    let output = re.replace_all(&buffer, |caps: &Captures| {
+    let output = re.replace_all(&buffer, |caps: &Captures<'_>| {
         match caps.name("pre") {
             Some(pre_section) => format!("{}", pre_section.to_owned()),
             None => {

tools/src/bin/remove_links.rs

@@ -8,7 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-extern crate regex;
+
 
 use std::io;
 use std::io::{Read, Write};
@@ -26,7 +26,7 @@ fn main () {
     // capture all links and link references
     let regex = r"\[([^\]]+)\](?:(?:\[([^\]]+)\])|(?:\([^\)]+\)))(?i)<!-- ignore -->";
     let link_regex = Regex::new(regex).unwrap();
-    let first_pass = link_regex.replace_all(&buffer, |caps: &Captures| {
+    let first_pass = link_regex.replace_all(&buffer, |caps: &Captures<'_>| {
 
         // save the link reference we want to delete
         if let Some(reference) = caps.at(2) {
@@ -39,7 +39,7 @@ fn main () {
 
     // search for the references we need to delete
     let ref_regex = Regex::new(r"\n\[([^\]]+)\]:\s.*\n").unwrap();
-    let out = ref_regex.replace_all(&first_pass, |caps: &Captures| {
+    let out = ref_regex.replace_all(&first_pass, |caps: &Captures<'_>| {
         let capture = caps.at(1).unwrap().to_owned();
 
         // check if we've marked this reference for deletion...

tools/src/bin/remove_markup.rs

@@ -8,7 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-extern crate regex;
+
 use std::io;
 use std::io::{Read, Write};
 use regex::{Regex, Captures};
@@ -50,7 +50,7 @@ fn remove_markup(input: String) -> String {
         // Remove the span around filenames and captions
         } else {
             let result = regexen.iter().fold(line.to_string(), |result, regex| {
-                regex.replace_all(&result, |caps: &Captures| {
+                regex.replace_all(&result, |caps: &Captures<'_>| {
                     caps.at(1).unwrap().to_owned()
                 })
             });