comm: add --output-delimiter

comm/comm.rs

@@ -21,21 +21,27 @@ use std::path::Path;
 static NAME : &'static str = "comm";
 static VERSION : &'static str = "1.0.0";
 
-fn delim(col: int, opts: &getopts::Matches) -> ~str {
+fn mkdelim(col: uint, opts: &getopts::Matches) -> StrBuf {
     let mut s = StrBuf::new();
+    let delim = match opts.opt_str("output-delimiter") {
+        Some(d) => d.clone(),
+        None => "\t".to_strbuf(),
+    };
 
     if col > 1 && !opts.opt_present("1") {
-        s.push_str("\t");
+        s.push_str(delim.as_slice());
     }
     if col > 2 && !opts.opt_present("2") {
-        s.push_str("\t");
+        s.push_str(delim.as_slice());
     }
 
-    s.to_owned()
+    s
 }
 
 fn comm(a: &mut Box<Buffer>, b: &mut Box<Buffer>, opts: &getopts::Matches) {
 
+    let delim = Vec::from_fn(4, |col| mkdelim(col, opts));
+
     let mut ra = a.read_line();
     let mut rb = b.read_line();
 
@@ -50,19 +56,19 @@ fn comm(a: &mut Box<Buffer>, b: &mut Box<Buffer>, opts: &getopts::Matches) {
         match ord {
             Less => {
                 if !opts.opt_present("1") {
-                    print!("{}{}", delim(1, opts), ra.unwrap());
+                    print!("{}{}", delim.get(1), ra.unwrap());
                 }
                 ra = a.read_line();
             }
             Greater => {
                 if !opts.opt_present("2") {
-                    print!("{}{}", delim(2, opts), rb.unwrap());
+                    print!("{}{}", delim.get(2), rb.unwrap());
                 }
                 rb = b.read_line();
             }
             Equal => {
                 if !opts.opt_present("3") {
-                    print!("{}{}", delim(3, opts), ra.unwrap());
+                    print!("{}{}", delim.get(3), ra.unwrap());
                 }
                 ra = a.read_line();
                 rb = b.read_line();
@@ -87,6 +93,7 @@ pub fn main() {
         getopts::optflag("1", "", "suppress column 1 (lines uniq to FILE1)"),
         getopts::optflag("2", "", "suppress column 2 (lines uniq to FILE2)"),
         getopts::optflag("3", "", "suppress column 3 (lines that appear in both files)"),
+        getopts::optopt("", "output-delimiter", "separate columns with STR", "STR"),
         getopts::optflag("h", "help", "display this help and exit"),
         getopts::optflag("V", "version", "output version information and exit"),
     ];