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authorAdam Carpenter <53hornet@gmail.com>2019-03-27 15:32:37 -0400
committerAdam Carpenter <53hornet@gmail.com>2019-03-27 15:32:37 -0400
commit67cdcc2e12118becb823e20a40cc2687f2b8425a (patch)
treeed92c3234b89079e6d4cf36f5e80c5ffa79def48 /rust-book/minigrep/src
parente25482fca375d318a39c3b54db396b0db6e0b263 (diff)
downloadlearning-rust-67cdcc2e12118becb823e20a40cc2687f2b8425a.tar.xz
learning-rust-67cdcc2e12118becb823e20a40cc2687f2b8425a.zip
Started Rust in Action MEAP.
Diffstat (limited to 'rust-book/minigrep/src')
-rwxr-xr-xrust-book/minigrep/src/lib.rs96
-rwxr-xr-xrust-book/minigrep/src/main.rs17
2 files changed, 113 insertions, 0 deletions
diff --git a/rust-book/minigrep/src/lib.rs b/rust-book/minigrep/src/lib.rs
new file mode 100755
index 0000000..bb8b4d7
--- /dev/null
+++ b/rust-book/minigrep/src/lib.rs
@@ -0,0 +1,96 @@
+use std::env;
+use std::error::Error;
+use std::fs;
+
+pub struct Config {
+ pub query: String,
+ pub filename: String,
+ pub case_sensitive: bool,
+}
+
+impl Config {
+
+ pub fn new(mut args: std::env::Args) -> Result<Config, &'static str> {
+ args.next();
+
+ let query = match args.next() {
+ Some(arg) => arg,
+ None => return Err("Didn't get a query string"),
+ };
+
+ let filename = match args.next() {
+ Some(arg) => arg,
+ None => return Err("Didn't get a filename"),
+ };
+
+ let case_sensitive = env::var("CASE_INSENSITIVE").is_err();
+
+ Ok(Config { query, filename, case_sensitive })
+ }
+
+}
+
+pub fn run(config: Config) -> Result<(), Box<dyn Error>> {
+ let contents = fs::read_to_string(config.filename)?;
+
+ let results = if config.case_sensitive {
+ search(&config.query, &contents)
+ }
+ else {
+ search_case_insensitive(&config.query, &contents)
+ };
+
+ for line in results {
+ println!("{}", line);
+ }
+
+ Ok(())
+}
+
+fn search<'a>(query: &str, contents: &'a str) -> Vec<&'a str> {
+ contents.lines()
+ .filter(|line| line.contains(query))
+ .collect()
+}
+
+fn search_case_insensitive<'a>(query: &str, contents: &'a str) -> Vec<&'a str> {
+ contents.lines()
+ .filter(|line| line.to_lowercase()
+ .contains(&query.to_lowercase()))
+ .collect()
+}
+
+#[cfg(test)]
+mod tests {
+ use super::*;
+
+ #[test]
+ fn case_sensitive() {
+ let query = "duct";
+ let contents = "\
+Rust:
+safe, fast, productive.
+Pick three.
+Duct tape.";
+
+ assert_eq!(
+ vec!["safe, fast, productive."],
+ search(query, contents)
+ );
+ }
+
+ #[test]
+ fn case_insensitive() {
+ let query = "rUsT";
+ let contents = "\
+Rust:
+safe, fast, productive.
+Pick three.
+Trust me.";
+
+ assert_eq!(
+ vec!["Rust:", "Trust me."],
+ search_case_insensitive(query, contents)
+ );
+ }
+}
diff --git a/rust-book/minigrep/src/main.rs b/rust-book/minigrep/src/main.rs
new file mode 100755
index 0000000..c752da1
--- /dev/null
+++ b/rust-book/minigrep/src/main.rs
@@ -0,0 +1,17 @@
+use std::process;
+use std::env;
+
+use minigrep;
+use minigrep::Config;
+
+fn main() {
+ let config = Config::new(env::args()).unwrap_or_else(|err| {
+ eprintln!("Problem parsing arguments: {}", err);
+ process::exit(1);
+ });
+ if let Err(e) = minigrep::run(config) {
+ eprintln!("Application error: {}", e);
+ process::exit(1);
+ }
+}
+