From 9407af5684ca5602df51c4edddc428db7fc98417 Mon Sep 17 00:00:00 2001 From: Vincent Ambo Date: Thu, 11 Aug 2022 11:55:59 +0300 Subject: refactor(tvix/eval): encapsulate list construction in value::list Ensuring that the implementation is not leaking out of the module lets us keep things open for optimisations (e.g. empty list or pairs through tuples). Change-Id: I18fd9b7740f28c55736471e16c6b4095a05dd6d0 Reviewed-on: https://cl.tvl.fyi/c/depot/+/6145 Tested-by: BuildkiteCI Reviewed-by: sterni --- tvix/eval/src/vm.rs | 21 +++++---------------- 1 file changed, 5 insertions(+), 16 deletions(-) (limited to 'tvix/eval/src/vm.rs') diff --git a/tvix/eval/src/vm.rs b/tvix/eval/src/vm.rs index 540845d2c668..a64e0b337aea 100644 --- a/tvix/eval/src/vm.rs +++ b/tvix/eval/src/vm.rs @@ -150,7 +150,11 @@ impl VM { self.push(Value::Attrs(Rc::new(lhs.update(&rhs)))) } - OpCode::OpList(count) => self.run_list(count)?, + OpCode::OpList(count) => { + let list = + NixList::construct(count, self.stack.split_off(self.stack.len() - count)); + self.push(Value::List(list)); + } OpCode::OpConcat => { let rhs = self.pop().as_list()?; @@ -204,21 +208,6 @@ impl VM { self.push(Value::String(out.into())); Ok(()) } - - // Construct runtime representation of a list. Because the list - // items are on the stack in reverse order, the vector is created - // initialised and elements are directly assigned to their - // respective indices. - fn run_list(&mut self, count: usize) -> EvalResult<()> { - let mut list = vec![Value::Null; count]; - - for idx in 0..count { - list[count - idx - 1] = self.pop(); - } - - self.push(Value::List(NixList(list))); - Ok(()) - } } pub fn run_chunk(chunk: Chunk) -> EvalResult { -- cgit 1.4.1