variable command

2 files changed, 29 insertions, 0 deletions

diff --git a/src/run/builtin.rs b/src/run/builtin.rs
index 99e0103..141357f 100644
--- a/src/run/builtin.rs
+++ b/src/run/builtin.rs
@@ -392,3 +392,31 @@ impl Builtin for null {
         Ok(())
     }
 }
+
+pub struct var;
+impl Builtin for var {
+    fn name(&self) -> &str {
+        "$"
+    }
+
+    fn io(
+        &self,
+        session: Arc<Mutex<Session>>,
+        args: &[BString],
+        _stdin: &mut dyn Read,
+        stdout: &mut dyn Write,
+    ) -> Result {
+        if args.is_empty() {
+            return Err(Error::Exit(-1));
+        } else if args.len() > 1 {
+            return Err(Error::Exit(-2));
+        }
+        let se = session.lock().unwrap();
+        if let Some(val) = se.vars.get(&args[0]) {
+            stdout.write_all(val.as_slice())?;
+            Ok(())
+        } else {
+            Err(Error::Exit(1))
+        }
+    }
+}
diff --git a/src/run/mod.rs b/src/run/mod.rs
index 5605639..679dd44 100644
--- a/src/run/mod.rs
+++ b/src/run/mod.rs
@@ -493,6 +493,7 @@ const BUILTINS: &[&'static dyn Builtin] = &[
     &builtin::escape,
     &builtin::parse,
     &builtin::null,
+    &builtin::var,
 ];
 
 pub fn builtin_map() -> HashMap<BString, &'static dyn Builtin> {