Port comb tool

Author: DaTa-

comb/Cargo.lock

@@ -0,0 +1,7 @@
+[package]
+name = "comb"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
+clap = { version = "3.2.12", features = ["derive"] }

comb/Cargo.toml

@@ -0,0 +1,57 @@
+use std::{
+    fs::File,
+    io::{self, BufRead, BufReader, Seek},
+    mem,
+    path::PathBuf,
+};
+
+use clap::Parser;
+
+/// Combine the lines from two files in every combination
+#[derive(Debug, Parser)]
+#[clap(about, arg_required_else_help(true))]
+struct Args {
+    /// Flip mode (order by suffix)
+    #[clap(short, long)]
+    flip: bool,
+
+    /// String to place between prefix and suffix
+    #[clap(short, long, value_parser, default_value_t)]
+    separator: String,
+
+    /// Path to a text file with each line representing a prefix
+    #[clap(value_parser)]
+    prefixfile: PathBuf,
+
+    /// Same as prefix file, but for suffixes
+    #[clap(value_parser)]
+    suffixfile: PathBuf,
+}
+
+fn main() -> io::Result<()> {
+    let Args {
+        flip,
+        separator,
+        prefixfile,
+        suffixfile,
+    } = Args::parse();
+    let (mut outer, mut inner) = (prefixfile, suffixfile);
+    if flip {
+        mem::swap(&mut outer, &mut inner);
+    }
+    let outer = BufReader::new(File::open(outer)?);
+    let mut inner = BufReader::new(File::open(inner)?);
+    for outer in outer.lines() {
+        let outer = outer?;
+        inner.seek(io::SeekFrom::Start(0))?;
+        for inner in (&mut inner).lines() {
+            let inner = inner?;
+            let (mut prefix, mut suffix) = (&outer, &inner);
+            if flip {
+                mem::swap(&mut prefix, &mut suffix);
+            }
+            println!("{prefix}{separator}{suffix}");
+        }
+    }
+    Ok(())
+}