diff --git a/crates/lang/src/parser/grammar/expression.rs b/crates/lang/src/parser/grammar/expression.rs
index 3f3a43e..2d3460c 100644
--- a/crates/lang/src/parser/grammar/expression.rs
+++ b/crates/lang/src/parser/grammar/expression.rs
@@ -2,49 +2,9 @@ use crate::parser::{syntax_kind::SyntaxKind::*, CompletedMarker, Parser};
 
 use self::{collection::collection, instruction::instr, lit::literal};
 
+mod collection;
 mod instruction;
 mod lit;
-mod collection {
-    use enumset::enum_set;
-
-    use crate::parser::{
-        syntax_kind::{SyntaxKind::*, TokenSet},
-        CompletedMarker, Parser,
-    };
-
-    use self::{attr_set::attr_set, matrix::matrix, vec::vec};
-
-    const COLLECTION_START: TokenSet = enum_set!(MAT_KW | L_BRACK | L_BRACE);
-
-    pub fn collection(p: &mut Parser) -> Option<CompletedMarker> {
-        if !COLLECTION_START.contains(p.current()) {
-            return None;
-        }
-
-        Some(match p.current() {
-            MAT_KW => matrix(p),
-            L_BRACK => vec(p),
-            L_BRACE => attr_set(p),
-            _ => unreachable!(),
-        })
-    }
-
-    mod matrix;
-    mod vec {
-        use crate::parser::{CompletedMarker, Parser};
-
-        pub fn vec(p: &mut Parser) -> CompletedMarker {
-            todo!()
-        }
-    }
-    mod attr_set {
-        use crate::parser::{CompletedMarker, Parser};
-
-        pub fn attr_set(p: &mut Parser) -> CompletedMarker {
-            todo!()
-        }
-    }
-}
 
 pub fn expression(p: &mut Parser) -> Option<CompletedMarker> {
     let expr = p.start("expr");
diff --git a/crates/lang/src/parser/grammar/expression/collection.rs b/crates/lang/src/parser/grammar/expression/collection.rs
new file mode 100644
index 0000000..0b525ad
--- /dev/null
+++ b/crates/lang/src/parser/grammar/expression/collection.rs
@@ -0,0 +1,27 @@
+use enumset::enum_set;
+
+use crate::parser::{
+    syntax_kind::{SyntaxKind::*, TokenSet},
+    CompletedMarker, Parser,
+};
+
+use self::{attr_set::attr_set, matrix::matrix, vec::vec};
+
+mod attr_set;
+mod matrix;
+mod vec;
+
+const COLLECTION_START: TokenSet = enum_set!(MAT_KW | L_BRACK | L_BRACE);
+
+pub fn collection(p: &mut Parser) -> Option<CompletedMarker> {
+    if !COLLECTION_START.contains(p.current()) {
+        return None;
+    }
+
+    Some(match p.current() {
+        MAT_KW => matrix(p),
+        L_BRACK => vec(p),
+        L_BRACE => attr_set(p),
+        _ => unreachable!(),
+    })
+}
diff --git a/crates/lang/src/parser/grammar/expression/collection/attr_set.rs b/crates/lang/src/parser/grammar/expression/collection/attr_set.rs
new file mode 100644
index 0000000..a71ee7f
--- /dev/null
+++ b/crates/lang/src/parser/grammar/expression/collection/attr_set.rs
@@ -0,0 +1,5 @@
+use crate::parser::{CompletedMarker, Parser};
+
+pub fn attr_set(p: &mut Parser) -> CompletedMarker {
+    todo!()
+}
diff --git a/crates/lang/src/parser/grammar/expression/collection/vec.rs b/crates/lang/src/parser/grammar/expression/collection/vec.rs
new file mode 100644
index 0000000..76f3684
--- /dev/null
+++ b/crates/lang/src/parser/grammar/expression/collection/vec.rs
@@ -0,0 +1,5 @@
+use crate::parser::{CompletedMarker, Parser};
+
+pub fn vec(p: &mut Parser) -> CompletedMarker {
+    todo!()
+}