Add basic functionality

Cargo.toml

@@ -6,3 +6,4 @@ edition = "2021"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
+clap = {version = "3.1.17", features = ["derive"]}

src/main.rs

@@ -1,5 +1,45 @@
-fn main() {
-    println!("Hello, world!");
+use std::fs::{File, read_to_string};
+use std::io::{BufWriter, Error, Write};
+use clap::Parser;
+
+fn main() -> Result<(), Error> {
+    let args = Args::parse();
+
+    let wordlist = read_to_string(args.filepath)?;
+    let mut list: Vec<&str> = wordlist.split_ascii_whitespace().collect();
+
+    let lowerbound = list.iter().position(|&x| x.contains("\\begin{acronym}"));
+    let upperbound = list.iter().position(|&x| x.contains("\\end{acronym}"));
+
+    match (lowerbound, upperbound) {
+        (Some(lower), Some(upper)) => {
+            println!("Sort range {}-{}", lower, upper);
+            sort_range(lower + 1, upper, &mut list)
+        },
+        _ => {
+            println!("No bounds found.");
+            ()
+        }
+    }
+
+    let mut writer = BufWriter::new(File::create(args.filepath)?);
+    writer.write(list.join("\n").as_bytes())?;
+    println!("Done.");
+
+    Ok(())
+}
+
+fn sort_range(lowerbound: usize, upperbound: usize, list: &mut Vec<&str>) {
+    list[lowerbound..upperbound].sort_unstable();
+}
+
+/// Sorts the acronym block of a .tex file
+#[derive(Parser, Debug)]
+#[clap(author, version, about, long_about = None)]
+struct Args {
+    /// The filepath to the .tex file
+    #[clap(short, long)]
+    filepath: String,
 }