fixed heredocs using the same expansion pathway as regular strings

implemented backtick command subs

deferred heredoc expansion until redir time instead of parse time

implemented "$*" expansions

function defs like 'func   ()  { }' now parse correctly

fixed conjunctions short circuiting instead of skipping

src/state.rs

@@ -1330,6 +1330,15 @@ impl VarTab {
         .get(&ShellParam::Status)
         .map(|s| s.to_string())
         .unwrap_or("0".into()),
+			ShellParam::AllArgsStr => {
+				let ifs = get_separator();
+				self
+					.params
+					.get(&ShellParam::AllArgs)
+					.map(|s| s.replace(markers::ARG_SEP, &ifs).to_string())
+					.unwrap_or_default()
+			}
+
       _ => self
         .params
         .get(&param)
@@ -1842,6 +1851,15 @@ pub fn change_dir<P: AsRef<Path>>(dir: P) -> ShResult<()> {
   Ok(())
 }
 
+pub fn get_separator() -> String {
+	env::var("IFS")
+		.unwrap_or(String::from(" "))
+		.chars()
+		.next()
+		.unwrap()
+		.to_string()
+}
+
 pub fn get_status() -> i32 {
   read_vars(|v| v.get_param(ShellParam::Status))
     .parse::<i32>()