1 files changed, 68 insertions, 0 deletions
diff --git a/third_party/rust/regex/examples/shootout-regex-dna.rs b/third_party/rust/regex/examples/shootout-regex-dna.rs
new file mode 100644
index 0000000000..b96518e4c4
--- /dev/null
+++ b/third_party/rust/regex/examples/shootout-regex-dna.rs
@@ -0,0 +1,68 @@
+// The Computer Language Benchmarks Game
+// https://benchmarksgame-team.pages.debian.net/benchmarksgame/
+//
+// contributed by the Rust Project Developers
+// contributed by TeXitoi
+// contributed by BurntSushi
+
+use std::io::{self, Read};
+use std::sync::Arc;
+use std::thread;
+
+macro_rules! regex {
+    ($re:expr) => {
+        ::regex::Regex::new($re).unwrap()
+    };
+}
+
+fn main() {
+    let mut seq = String::with_capacity(51 * (1 << 20));
+    io::stdin().read_to_string(&mut seq).unwrap();
+    let ilen = seq.len();
+
+    seq = regex!(">[^\n]*\n|\n").replace_all(&seq, "").into_owned();
+    let clen = seq.len();
+    let seq_arc = Arc::new(seq.clone());
+
+    let variants = vec![
+        regex!("agggtaaa|tttaccct"),
+        regex!("[cgt]gggtaaa|tttaccc[acg]"),
+        regex!("a[act]ggtaaa|tttacc[agt]t"),
+        regex!("ag[act]gtaaa|tttac[agt]ct"),
+        regex!("agg[act]taaa|ttta[agt]cct"),
+        regex!("aggg[acg]aaa|ttt[cgt]ccct"),
+        regex!("agggt[cgt]aa|tt[acg]accct"),
+        regex!("agggta[cgt]a|t[acg]taccct"),
+        regex!("agggtaa[cgt]|[acg]ttaccct"),
+    ];
+    let mut counts = vec![];
+    for variant in variants {
+        let seq = seq_arc.clone();
+        let restr = variant.to_string();
+        let future = thread::spawn(move || variant.find_iter(&seq).count());
+        counts.push((restr, future));
+    }
+
+    let substs = vec![
+        (regex!("B"), "(c|g|t)"),
+        (regex!("D"), "(a|g|t)"),
+        (regex!("H"), "(a|c|t)"),
+        (regex!("K"), "(g|t)"),
+        (regex!("M"), "(a|c)"),
+        (regex!("N"), "(a|c|g|t)"),
+        (regex!("R"), "(a|g)"),
+        (regex!("S"), "(c|g)"),
+        (regex!("V"), "(a|c|g)"),
+        (regex!("W"), "(a|t)"),
+        (regex!("Y"), "(c|t)"),
+    ];
+    let mut seq = seq;
+    for (re, replacement) in substs {
+        seq = re.replace_all(&seq, replacement).into_owned();
+    }
+
+    for (variant, count) in counts {
+        println!("{} {}", variant, count.join().unwrap());
+    }
+    println!("\n{}\n{}\n{}", ilen, clen, seq.len());
+}