1 files changed, 19 insertions, 6 deletions

diff --git a/src/run/mod.rs b/src/run/mod.rs
index f767434..0b9aef8 100644
--- a/src/run/mod.rs
+++ b/src/run/mod.rs
@@ -8,6 +8,7 @@ use crate::*;
 
 mod builtin;
 
+#[derive(Debug)]
 enum ExecError {
     UnknownVariable(BString),
     ExecError(i32),
@@ -16,6 +17,7 @@ enum ExecError {
 #[derive(Clone)]
 struct Executor {
     se: Arc<Mutex<Session>>,
+    args: Option<Vec<BString>>,
 }
 
 impl Executor {
@@ -121,8 +123,16 @@ impl Executor {
                     threads.push(handle);
                 }
 
-                CommandKind::Fun(_ast) => {
-                    todo!()
+                CommandKind::Fun(ast) => {
+                    let mut this = self.clone();
+
+                    let mut args = Vec::with_capacity(cmd.args.len() + 1);
+                    args.push(cmd.cmd.clone());
+                    args.extend_from_slice(&cmd.args);
+                    this.args = Some(args);
+
+                    let ast = ast.expand(&mut this)?;
+                    this.execute(ast, prev_reader, writer).unwrap();
                 }
             }
 
@@ -206,9 +216,12 @@ impl parse::Expander for Executor {
                 .ok()
                 .and_then(|x| x.parse::<usize>().ok())
             {
-                match std::env::args_os().skip(x).next() {
-                    Some(arg) => return Ok(arg.into_encoded_bytes()),
-                    None => (),
+                if let Some(args) = &self.args {
+                    if x < args.len() {
+                        return Ok(args[x].clone());
+                    }
+                } else if let Some(arg) = std::env::args_os().skip(x).next() {
+                    return Ok(arg.into_encoded_bytes());
                 }
             }
         }
@@ -239,7 +252,7 @@ impl parse::Expander for Executor {
 }
 
 fn exec(se: Arc<Mutex<Session>>, ast: Ast<PreExpansion>) -> Result<(), ExecError> {
-    let mut exec = Executor { se };
+    let mut exec = Executor { se, args: None };
     let ast = ast.expand(&mut exec)?;
     exec.execute(ast, None, None)
 }