From 7adc3f37dd9c43dfdd16aebb84e18a0ac27e8973 Mon Sep 17 00:00:00 2001
From: Sergei Zharinov <zharinov@users.noreply.github.com>
Date: Mon, 5 Jan 2026 22:28:20 -0300
Subject: [PATCH] refactor: merge alternation wrapper effects into body
 instructions

---
 crates/plotnik-lib/src/compile/capture.rs     |  21 ++-
 crates/plotnik-lib/src/compile/expressions.rs |  23 ++-
 crates/plotnik-lib/src/compile/quantifier.rs  |   2 +
 crates/plotnik-lib/src/compile/scope.rs       |  63 ++++---
 crates/plotnik-lib/src/compile/sequences.rs   | 164 ++++++++----------
 ...n_tests__alternations_captured_tagged.snap |  10 +-
 ...gen_tests__alternations_in_quantifier.snap |  30 ++--
 ...__codegen_tests__alternations_labeled.snap |  10 +-
 ...en_tests__alternations_null_injection.snap |   8 +-
 ...ternations_tagged_in_field_constraint.snap |  12 +-
 ...ternations_tagged_with_definition_ref.snap |  12 +-
 ...codegen_tests__alternations_unlabeled.snap |   8 +-
 ...s__captures_enum_with_type_annotation.snap |  10 +-
 ...tests__comprehensive_multi_definition.snap |  10 +-
 ..._codegen_tests__definitions_reference.snap |   8 +-
 ...it__codegen_tests__fields_alternation.snap |  10 +-
 ...emit__codegen_tests__recursion_simple.snap |  16 +-
 ...sts__recursion_with_structured_result.snap |  16 +-
 ..._engine_tests__recursion_member_chain.snap |  60 +++----
 ...on_call_searches_for_field_constraint.snap |  52 +++---
 20 files changed, 246 insertions(+), 299 deletions(-)

diff --git a/crates/plotnik-lib/src/compile/capture.rs b/crates/plotnik-lib/src/compile/capture.rs
index 507df877..0fc7c943 100644
--- a/crates/plotnik-lib/src/compile/capture.rs
+++ b/crates/plotnik-lib/src/compile/capture.rs
@@ -13,15 +13,26 @@ use crate::parser::ast::{self, Expr};
 use super::Compiler;
 use super::navigation::{inner_creates_scope, is_star_or_plus_quantifier, is_truly_empty_scope};
 
-/// Capture effects to attach to the innermost match instruction.
+/// Capture effects to attach to match instructions.
 ///
-/// Instead of emitting a separate epsilon transition for capture effects,
+/// Instead of emitting separate epsilon transitions for wrapper effects,
 /// these effects are propagated through the compilation chain and attached
-/// directly to the match instruction that captures the node.
+/// directly to match instructions.
+///
+/// For sequences `{a b c}`:
+/// - `pre` effects go on the first item (entry)
+/// - `post` effects go on the last item (exit)
+///
+/// For tagged alternations `[A: body]`:
+/// - `pre` contains `Enum(variant)` for branch entry
+/// - `post` contains `EndEnum` for branch exit
 #[derive(Clone, Default)]
 pub struct CaptureEffects {
-    /// Effects to place as post_effects on the matching instruction.
-    /// Typically: [Node/Text, Set(member)] or [Node/Text, Push]
+    /// Effects to place as pre_effects on the entry instruction.
+    /// Used for: Enum(variant) in tagged alternations.
+    pub pre: Vec<EffectIR>,
+    /// Effects to place as post_effects on the exit instruction.
+    /// Typically: [Node/Text, Set(member)], [Push], or [EndEnum].
     pub post: Vec<EffectIR>,
 }
 
diff --git a/crates/plotnik-lib/src/compile/expressions.rs b/crates/plotnik-lib/src/compile/expressions.rs
index a7f5b1d4..97fba557 100644
--- a/crates/plotnik-lib/src/compile/expressions.rs
+++ b/crates/plotnik-lib/src/compile/expressions.rs
@@ -46,7 +46,7 @@ impl Compiler<'_> {
                 nav,
                 node_type,
                 node_field: None,
-                pre_effects: vec![],
+                pre_effects: capture.pre,
                 neg_fields,
                 post_effects: capture.post,
                 successors: vec![exit],
@@ -115,7 +115,7 @@ impl Compiler<'_> {
             nav,
             node_type,
             node_field: None,
-            pre_effects: vec![],
+            pre_effects: capture.pre,
             neg_fields,
             post_effects: capture.post,
             successors: vec![items_entry],
@@ -199,7 +199,7 @@ impl Compiler<'_> {
             nav,
             node_type,
             node_field: None,
-            pre_effects: vec![],
+            pre_effects: capture.pre,
             neg_fields,
             post_effects: capture.post,
             successors: vec![down_wildcard],
@@ -230,7 +230,7 @@ impl Compiler<'_> {
             nav,
             node_type,
             node_field: None,
-            pre_effects: vec![],
+            pre_effects: capture.pre,
             neg_fields: vec![],
             post_effects: capture.post,
             successors: vec![exit],
@@ -280,7 +280,8 @@ impl Compiler<'_> {
 
         let nav = nav_override.unwrap_or(Nav::Stay);
 
-        if needs_scope {
+        // Call instructions don't have pre_effects, so emit epsilon if needed
+        let call_entry = if needs_scope {
             // Captured ref returning struct: Obj → Call → EndObj → Set → exit
             // The Obj creates an isolated scope for the definition's internal captures.
             let set_step = self.emit_effects_epsilon(exit, capture.post, CaptureEffects::default());
@@ -295,7 +296,14 @@ impl Compiler<'_> {
         } else {
             // Uncaptured ref: just Call → exit (def's Sets go to parent scope)
             self.emit_call(nav, field_override, exit, target)
+        };
+
+        if capture.pre.is_empty() {
+            return call_entry;
         }
+
+        // Wrap with pre-effects epsilon (e.g., Enum for tagged alternations)
+        self.emit_effects_epsilon(call_entry, capture.pre, CaptureEffects::default())
     }
 
     /// Compile a field constraint with capture effects (passed to inner pattern).
@@ -500,7 +508,10 @@ impl Compiler<'_> {
             &inner,
             exit,
             nav_override,
-            CaptureEffects { post: combined },
+            CaptureEffects {
+                pre: outer_capture.pre,
+                post: combined,
+            },
         )
     }
 
diff --git a/crates/plotnik-lib/src/compile/quantifier.rs b/crates/plotnik-lib/src/compile/quantifier.rs
index 93f6b701..497852d9 100644
--- a/crates/plotnik-lib/src/compile/quantifier.rs
+++ b/crates/plotnik-lib/src/compile/quantifier.rs
@@ -193,6 +193,7 @@ impl Compiler<'_> {
             // Non-array capture: build capture effects and recurse
             let capture_effects = self.build_capture_effects(cap, Some(&inner));
             let mut combined = CaptureEffects {
+                pre: capture.pre.clone(),
                 post: capture_effects,
             };
             combined.post.extend(capture.post);
@@ -259,6 +260,7 @@ impl Compiler<'_> {
         let skip_endarr = self.emit_endarr_step(&capture_effects, &outer_capture.post, skip_exit);
 
         let push_effects = CaptureEffects {
+            pre: vec![],
             post: if self.quantifier_needs_node_for_push(inner) {
                 let opcode = if cap.has_string_annotation() {
                     EffectOpcode::Text
diff --git a/crates/plotnik-lib/src/compile/scope.rs b/crates/plotnik-lib/src/compile/scope.rs
index e6dfafbc..0ad621aa 100644
--- a/crates/plotnik-lib/src/compile/scope.rs
+++ b/crates/plotnik-lib/src/compile/scope.rs
@@ -145,6 +145,7 @@ impl Compiler<'_> {
 
             // Compile inner with capture_effects on the match instruction
             let inner_capture = CaptureEffects {
+                pre: outer_capture.pre,
                 post: capture_effects,
             };
             return self.compile_expr_inner(inner, actual_exit, nav_override, inner_capture);
@@ -168,7 +169,9 @@ impl Compiler<'_> {
         }));
 
         // Compile inner WITH capture_effects on the match instruction
+        // Note: pre effects don't propagate through Obj/EndObj scope wrapper
         let inner_capture = CaptureEffects {
+            pre: vec![],
             post: capture_effects,
         };
         let inner_entry = self.with_scope(scope_type_id.unwrap(), |this| {
@@ -220,6 +223,7 @@ impl Compiler<'_> {
         }));
 
         let push_effects = CaptureEffects {
+            pre: vec![],
             post: if self.quantifier_needs_node_for_push(inner) {
                 // Use Text if the capture has `:: string` annotation, else Node
                 let opcode = if use_text_for_elements {
@@ -491,39 +495,34 @@ impl Compiler<'_> {
         use crate::bytecode::MAX_MATCH_PAYLOAD_SLOTS;
 
         if successors.len() <= MAX_MATCH_PAYLOAD_SLOTS {
-            self.instructions.push(Instruction::Match(MatchIR {
-                label,
-                nav: Nav::Stay,
-                node_type: None,
-                node_field: None,
-                pre_effects: vec![],
-                neg_fields: vec![],
-                post_effects: vec![],
-                successors,
-            }));
-        } else {
-            // Split: first (MAX-1) successors + intermediate for rest.
-            // This preserves priority order: VM tries s0, s1, ..., then intermediate.
-            let split_at = MAX_MATCH_PAYLOAD_SLOTS - 1;
-            let (first_batch, rest) = successors.split_at(split_at);
-
-            let intermediate = self.fresh_label();
-            self.emit_epsilon(intermediate, rest.to_vec());
-
-            let mut batch = first_batch.to_vec();
-            batch.push(intermediate);
-
-            self.instructions.push(Instruction::Match(MatchIR {
-                label,
-                nav: Nav::Stay,
-                node_type: None,
-                node_field: None,
-                pre_effects: vec![],
-                neg_fields: vec![],
-                post_effects: vec![],
-                successors: batch,
-            }));
+            self.push_epsilon(label, successors);
+            return;
         }
+
+        // Split: first (MAX-1) successors + intermediate for rest.
+        // This preserves priority order: VM tries s0, s1, ..., then intermediate.
+        let split_at = MAX_MATCH_PAYLOAD_SLOTS - 1;
+        let (first_batch, rest) = successors.split_at(split_at);
+
+        let intermediate = self.fresh_label();
+        self.emit_epsilon(intermediate, rest.to_vec());
+
+        let mut batch = first_batch.to_vec();
+        batch.push(intermediate);
+        self.push_epsilon(label, batch);
+    }
+
+    fn push_epsilon(&mut self, label: Label, successors: Vec<Label>) {
+        self.instructions.push(Instruction::Match(MatchIR {
+            label,
+            nav: Nav::Stay,
+            node_type: None,
+            node_field: None,
+            pre_effects: vec![],
+            neg_fields: vec![],
+            post_effects: vec![],
+            successors,
+        }));
     }
 
     /// Emit a wildcard navigation step that accepts any node.
diff --git a/crates/plotnik-lib/src/compile/sequences.rs b/crates/plotnik-lib/src/compile/sequences.rs
index 5b1502dc..a92fe104 100644
--- a/crates/plotnik-lib/src/compile/sequences.rs
+++ b/crates/plotnik-lib/src/compile/sequences.rs
@@ -9,7 +9,7 @@ use std::collections::BTreeMap;
 use plotnik_core::Symbol;
 
 use crate::analyze::type_check::{TypeId, TypeShape};
-use crate::bytecode::ir::{EffectIR, Instruction, Label, MatchIR, MemberRef};
+use crate::bytecode::ir::{EffectIR, Label, MemberRef};
 use crate::bytecode::{EffectOpcode, Nav};
 use crate::parser::ast::{self, Expr, SeqItem};
 
@@ -98,21 +98,31 @@ impl Compiler<'_> {
         }
 
         // Build chain in reverse: last expression exits to `exit`, each prior exits to next
-        // Capture effects go to the FIRST iteration (which is the last expression)
+        // Split capture effects: pre goes to FIRST item, post goes to LAST item
         let mut current_exit = exit;
-        let mut is_last = true;
-        for (expr_idx, nav_override) in nav_modes.into_iter().rev() {
+        let count = nav_modes.len();
+        for (i, (expr_idx, nav_override)) in nav_modes.into_iter().rev().enumerate() {
             let expr = items[expr_idx]
                 .as_expr()
                 .expect("nav_modes only contains expr indices");
-            if is_last {
-                // Last expression gets capture effects
-                current_exit =
-                    self.compile_expr_inner(expr, current_exit, nav_override, capture.clone());
-                is_last = false;
-            } else {
-                current_exit = self.compile_expr_with_nav(expr, current_exit, nav_override);
-            }
+
+            let is_last_expr = i == 0; // First in reversed loop = last in sequence
+            let is_first_expr = i == count - 1; // Last in reversed loop = first in sequence
+
+            let item_capture = CaptureEffects {
+                pre: if is_first_expr {
+                    capture.pre.clone()
+                } else {
+                    vec![]
+                },
+                post: if is_last_expr {
+                    capture.post.clone()
+                } else {
+                    vec![]
+                },
+            };
+
+            current_exit = self.compile_expr_inner(expr, current_exit, nav_override, item_capture);
         }
         current_exit
     }
@@ -239,101 +249,67 @@ impl Compiler<'_> {
                     .map(|(_, &(idx, type_id))| (idx, type_id))
                     .expect("variant must exist for labeled branch");
 
-                // Tagged branch: E(variant_ref) → body → EndE → exit
-                // Outer capture effects go on EndEnum, not on the branch body
-                let mut end_effects = vec![EffectIR::simple(EffectOpcode::EndEnum, 0)];
-                end_effects.extend(capture.post.iter().cloned());
-
-                let ende_step = self.fresh_label();
-                self.instructions.push(Instruction::Match(MatchIR {
-                    label: ende_step,
-                    nav: Nav::Stay,
-                    node_type: None,
-                    node_field: None,
-                    pre_effects: vec![],
-                    neg_fields: vec![],
-                    post_effects: end_effects,
-                    successors: vec![exit],
-                }));
-
-                // Compile body with variant's scope (no outer capture - it's on EndEnum)
-                let body_entry = self.with_scope(payload_type_id, |this| {
-                    this.compile_expr_inner(&body, ende_step, branch_nav, CaptureEffects::default())
-                });
-
-                // Create deferred member reference for the enum variant
-                // Uses parent enum type + relative index (enum variants don't bubble)
+                // Create Enum effect for branch entry
                 let e_effect = if let Some(type_id) = alt_type_id {
                     EffectIR::with_member(
                         EffectOpcode::Enum,
                         MemberRef::deferred_by_index(type_id, variant_idx),
                     )
                 } else {
-                    // Fallback: use absolute index (should not happen for well-formed queries)
                     EffectIR::simple(EffectOpcode::Enum, 0)
                 };
 
-                let e_step = self.fresh_label();
-                self.instructions.push(Instruction::Match(MatchIR {
-                    label: e_step,
-                    nav: Nav::Stay,
-                    node_type: None,
-                    node_field: None,
-                    pre_effects: vec![e_effect],
-                    neg_fields: vec![],
-                    post_effects: vec![],
-                    successors: vec![body_entry],
-                }));
-
-                successors.push(e_step);
-            } else {
-                // Untagged branch: compile body, then inject Null for missing captures
-                let branch_entry =
-                    self.compile_expr_inner(&body, exit, branch_nav, capture.clone());
+                // Build capture effects: Enum as pre, EndEnum + outer as post
+                let mut post_effects = vec![EffectIR::simple(EffectOpcode::EndEnum, 0)];
+                post_effects.extend(capture.post.iter().cloned());
 
-                let Some(fields) = merged_fields else {
-                    successors.push(branch_entry);
-                    continue;
+                let branch_capture = CaptureEffects {
+                    pre: vec![e_effect],
+                    post: post_effects,
                 };
-                let Some(alt_type) = alt_type_id else {
-                    successors.push(branch_entry);
-                    continue;
+
+                // Compile body with merged effects - no separate epsilon wrappers needed
+                let body_entry = self.with_scope(payload_type_id, |this| {
+                    this.compile_expr_inner(&body, exit, branch_nav, branch_capture)
+                });
+
+                successors.push(body_entry);
+            } else {
+                // Untagged branch: compile body with null injection for missing captures
+                let null_effects: Vec<_> =
+                    if let (Some(fields), Some(alt_type)) = (merged_fields, alt_type_id) {
+                        let branch_captures = Self::collect_captures(&body);
+                        fields
+                            .iter()
+                            .enumerate()
+                            .filter(|(_, (sym, _))| {
+                                !branch_captures.contains(self.interner.resolve(**sym))
+                            })
+                            .flat_map(|(idx, _)| {
+                                [
+                                    EffectIR::simple(EffectOpcode::Null, 0),
+                                    EffectIR::with_member(
+                                        EffectOpcode::Set,
+                                        MemberRef::deferred_by_index(alt_type, idx as u16),
+                                    ),
+                                ]
+                            })
+                            .collect()
+                    } else {
+                        vec![]
+                    };
+
+                // Merge null injection with outer capture effects
+                let mut pre = null_effects;
+                pre.extend(capture.pre.iter().cloned());
+
+                let branch_capture = CaptureEffects {
+                    pre,
+                    post: capture.post.clone(),
                 };
 
-                // Build Null effects for fields not captured by this branch
-                let branch_captures = Self::collect_captures(&body);
-                let null_effects: Vec<_> = fields
-                    .iter()
-                    .enumerate()
-                    .filter(|(_, (sym, _))| !branch_captures.contains(self.interner.resolve(**sym)))
-                    .flat_map(|(idx, _)| {
-                        [
-                            EffectIR::simple(EffectOpcode::Null, 0),
-                            EffectIR::with_member(
-                                EffectOpcode::Set,
-                                MemberRef::deferred_by_index(alt_type, idx as u16),
-                            ),
-                        ]
-                    })
-                    .collect();
-
-                if null_effects.is_empty() {
-                    successors.push(branch_entry);
-                    continue;
-                }
-
-                let null_step = self.fresh_label();
-                self.instructions.push(Instruction::Match(MatchIR {
-                    label: null_step,
-                    nav: Nav::Stay,
-                    node_type: None,
-                    node_field: None,
-                    pre_effects: null_effects,
-                    neg_fields: vec![],
-                    post_effects: vec![],
-                    successors: vec![branch_entry],
-                }));
-                successors.push(null_step);
+                let branch_entry = self.compile_expr_inner(&body, exit, branch_nav, branch_capture);
+                successors.push(branch_entry);
             }
         }
 
diff --git a/crates/plotnik-lib/src/emit/snapshots/plotnik_lib__emit__codegen_tests__alternations_captured_tagged.snap b/crates/plotnik-lib/src/emit/snapshots/plotnik_lib__emit__codegen_tests__alternations_captured_tagged.snap
index b5368902..36ebee8e 100644
--- a/crates/plotnik-lib/src/emit/snapshots/plotnik_lib__emit__codegen_tests__alternations_captured_tagged.snap
+++ b/crates/plotnik-lib/src/emit/snapshots/plotnik_lib__emit__codegen_tests__alternations_captured_tagged.snap
@@ -46,12 +46,8 @@ _ObjWrap:
 
 Test:
   06   ε                                    07
-  07   ε                                    16, 22
+  07   ε                                    12, 15
   09                                        ▶
   10   ε   [Set(M4)]                        09
-  12   ε   [EndEnum]                        10
-  14   !   (identifier) [Node Set(M0)]      12
-  16   ε   [Enum(M2)]                       14
-  18   ε   [EndEnum]                        10
-  20   !   (number) [Node Set(M1)]          18
-  22   ε   [Enum(M3)]                       20
+  12   !   [Enum(M2)] (identifier) [Node Set(M0) EndEnum]  10
+  15   !   [Enum(M3)] (number) [Node Set(M1) EndEnum]  10
diff --git a/crates/plotnik-lib/src/emit/snapshots/plotnik_lib__emit__codegen_tests__alternations_in_quantifier.snap b/crates/plotnik-lib/src/emit/snapshots/plotnik_lib__emit__codegen_tests__alternations_in_quantifier.snap
index e969187b..964c95fd 100644
--- a/crates/plotnik-lib/src/emit/snapshots/plotnik_lib__emit__codegen_tests__alternations_in_quantifier.snap
+++ b/crates/plotnik-lib/src/emit/snapshots/plotnik_lib__emit__codegen_tests__alternations_in_quantifier.snap
@@ -53,27 +53,23 @@ Test:
   06   ε                                    07
   07   !   (object)                         08
   08   ε   [Arr]                            10
-  10   ε                                    45, 20
+  10   ε                                    39, 20
   12   ε   [EndArr Set(M5)]                 14
   14   △                                    19
   15   ε   [EndObj Push]                    17
-  17   ε                                    51, 12
+  17   ε                                    45, 12
   19                                        ▶
   20   ε   [EndArr Set(M5)]                 19
   22   ε   [Set(M4)]                        15
-  24   ε   [EndEnum]                        22
-  26   !   (pair) [Node Set(M0)]            24
-  28   ε   [Enum(M2)]                       26
-  30   ε   [EndEnum]                        22
-  32   !   (shorthand_property_identifier) [Node Set(M1)]  30
-  34   ε   [Enum(M3)]                       32
-  36   ε                                    28, 34
-  38   ε   [Obj]                            36
+  24   !   [Enum(M2)] (pair) [Node Set(M0) EndEnum]  22
+  27   !   [Enum(M3)] (shorthand_property_identifier) [Node Set(M1) EndEnum]  22
+  30   ε                                    24, 27
+  32   ε   [Obj]                            30
+  34   ▷                                    37
+  35   ε                                    34, 20
+  37   ε                                    32, 35
+  39   ▽                                    37
   40   ▷                                    43
-  41   ε                                    40, 20
-  43   ε                                    38, 41
-  45   ▽                                    43
-  46   ▷                                    49
-  47   ε                                    46, 12
-  49   ε                                    38, 47
-  51   ▷                                    49
+  41   ε                                    40, 12
+  43   ε                                    32, 41
+  45   ▷                                    43
diff --git a/crates/plotnik-lib/src/emit/snapshots/plotnik_lib__emit__codegen_tests__alternations_labeled.snap b/crates/plotnik-lib/src/emit/snapshots/plotnik_lib__emit__codegen_tests__alternations_labeled.snap
index d3920e27..85f6e97a 100644
--- a/crates/plotnik-lib/src/emit/snapshots/plotnik_lib__emit__codegen_tests__alternations_labeled.snap
+++ b/crates/plotnik-lib/src/emit/snapshots/plotnik_lib__emit__codegen_tests__alternations_labeled.snap
@@ -46,11 +46,7 @@ _ObjWrap:
 
 Test:
   06   ε                                    07
-  07   ε                                    14, 20
+  07   ε                                    10, 13
   09                                        ▶
-  10   ε   [EndEnum]                        09
-  12   !   (identifier) [Node Set(M0)]      10
-  14   ε   [Enum(M2)]                       12
-  16   ε   [EndEnum]                        09
-  18   !   (number) [Node Set(M1)]          16
-  20   ε   [Enum(M3)]                       18
+  10   !   [Enum(M2)] (identifier) [Node Set(M0) EndEnum]  09
+  13   !   [Enum(M3)] (number) [Node Set(M1) EndEnum]  09
diff --git a/crates/plotnik-lib/src/emit/snapshots/plotnik_lib__emit__codegen_tests__alternations_null_injection.snap b/crates/plotnik-lib/src/emit/snapshots/plotnik_lib__emit__codegen_tests__alternations_null_injection.snap
index 399c8d54..ab0a7056 100644
--- a/crates/plotnik-lib/src/emit/snapshots/plotnik_lib__emit__codegen_tests__alternations_null_injection.snap
+++ b/crates/plotnik-lib/src/emit/snapshots/plotnik_lib__emit__codegen_tests__alternations_null_injection.snap
@@ -42,9 +42,7 @@ _ObjWrap:
 
 Test:
   06   ε                                    07
-  07   ε                                    12, 16
+  07   ε                                    10, 13
   09                                        ▶
-  10   !   (identifier) [Node Set(M0)]      09
-  12   ε   [Null Set(M1)]                   10
-  14   !   (number) [Node Set(M1)]          09
-  16   ε   [Null Set(M0)]                   14
+  10   !   [Null Set(M1)] (identifier) [Node Set(M0)]  09
+  13   !   [Null Set(M0)] (number) [Node Set(M1)]  09
diff --git a/crates/plotnik-lib/src/emit/snapshots/plotnik_lib__emit__codegen_tests__alternations_tagged_in_field_constraint.snap b/crates/plotnik-lib/src/emit/snapshots/plotnik_lib__emit__codegen_tests__alternations_tagged_in_field_constraint.snap
index 2e84b2ac..c219a955 100644
--- a/crates/plotnik-lib/src/emit/snapshots/plotnik_lib__emit__codegen_tests__alternations_tagged_in_field_constraint.snap
+++ b/crates/plotnik-lib/src/emit/snapshots/plotnik_lib__emit__codegen_tests__alternations_tagged_in_field_constraint.snap
@@ -48,12 +48,8 @@ Test:
   06   ε                                    07
   07   !   (foo)                            08
   08   ▽   field: _                         09
-  09   ε                                    16, 21
+  09   ε                                    12, 15
   11                                        ▶
-  12   ε   [EndEnum Set(M3)]                23
-  14   !   (x) [Node Set(M0)]               12
-  16   ε   [Enum(M1)]                       14
-  18   ε   [EndEnum Set(M3)]                23
-  20   !   (y)                              18
-  21   ε   [Enum(M2)]                       20
-  23   △                                    11
+  12   !   [Enum(M1)] (x) [Node Set(M0) EndEnum Set(M3)]  17
+  15   !   [Enum(M2)] (y) [EndEnum Set(M3)]  17
+  17   △                                    11
diff --git a/crates/plotnik-lib/src/emit/snapshots/plotnik_lib__emit__codegen_tests__alternations_tagged_with_definition_ref.snap b/crates/plotnik-lib/src/emit/snapshots/plotnik_lib__emit__codegen_tests__alternations_tagged_with_definition_ref.snap
index f5a2d9ca..eb29ed85 100644
--- a/crates/plotnik-lib/src/emit/snapshots/plotnik_lib__emit__codegen_tests__alternations_tagged_with_definition_ref.snap
+++ b/crates/plotnik-lib/src/emit/snapshots/plotnik_lib__emit__codegen_tests__alternations_tagged_with_definition_ref.snap
@@ -55,12 +55,12 @@ Inner:
 
 Test:
   10   ε                                    11
-  11   ε                                    19, 25
+  11   ε                                    23, 25
   13                                        ▶
   14   ε   [Set(M4)]                        13
   16   ε   [EndEnum]                        14
-  18   !   (Inner)                          06 : 16
-  19   ε   [Enum(M2)]                       18
-  21   ε   [EndEnum]                        14
-  23   !   (number) [Node Set(M1)]          21
-  25   ε   [Enum(M3)]                       23
+  18   ε   [EndObj]                         16
+  20   !   (Inner)                          06 : 18
+  21   ε   [Obj]                            20
+  23   ε   [Enum(M2)]                       21
+  25   !   [Enum(M3)] (number) [Node Set(M1) EndEnum]  14
diff --git a/crates/plotnik-lib/src/emit/snapshots/plotnik_lib__emit__codegen_tests__alternations_unlabeled.snap b/crates/plotnik-lib/src/emit/snapshots/plotnik_lib__emit__codegen_tests__alternations_unlabeled.snap
index 48490c6f..a0b142e7 100644
--- a/crates/plotnik-lib/src/emit/snapshots/plotnik_lib__emit__codegen_tests__alternations_unlabeled.snap
+++ b/crates/plotnik-lib/src/emit/snapshots/plotnik_lib__emit__codegen_tests__alternations_unlabeled.snap
@@ -42,9 +42,7 @@ _ObjWrap:
 
 Test:
   06   ε                                    07
-  07   ε                                    12, 16
+  07   ε                                    10, 13
   09                                        ▶
-  10   !   (identifier) [Node Set(M0)]      09
-  12   ε   [Null Set(M1)]                   10
-  14   !   (string) [Node Set(M1)]          09
-  16   ε   [Null Set(M0)]                   14
+  10   !   [Null Set(M1)] (identifier) [Node Set(M0)]  09
+  13   !   [Null Set(M0)] (string) [Node Set(M1)]  09
diff --git a/crates/plotnik-lib/src/emit/snapshots/plotnik_lib__emit__codegen_tests__captures_enum_with_type_annotation.snap b/crates/plotnik-lib/src/emit/snapshots/plotnik_lib__emit__codegen_tests__captures_enum_with_type_annotation.snap
index 458ede90..b0598e97 100644
--- a/crates/plotnik-lib/src/emit/snapshots/plotnik_lib__emit__codegen_tests__captures_enum_with_type_annotation.snap
+++ b/crates/plotnik-lib/src/emit/snapshots/plotnik_lib__emit__codegen_tests__captures_enum_with_type_annotation.snap
@@ -48,12 +48,8 @@ _ObjWrap:
 
 Test:
   06   ε                                    07
-  07   ε                                    16, 22
+  07   ε                                    12, 15
   09                                        ▶
   10   ε   [Set(M4)]                        09
-  12   ε   [EndEnum]                        10
-  14   !   (identifier) [Node Set(M0)]      12
-  16   ε   [Enum(M2)]                       14
-  18   ε   [EndEnum]                        10
-  20   !   (number) [Node Set(M1)]          18
-  22   ε   [Enum(M3)]                       20
+  12   !   [Enum(M2)] (identifier) [Node Set(M0) EndEnum]  10
+  15   !   [Enum(M3)] (number) [Node Set(M1) EndEnum]  10
diff --git a/crates/plotnik-lib/src/emit/snapshots/plotnik_lib__emit__codegen_tests__comprehensive_multi_definition.snap b/crates/plotnik-lib/src/emit/snapshots/plotnik_lib__emit__codegen_tests__comprehensive_multi_definition.snap
index c556823f..6d714f8e 100644
--- a/crates/plotnik-lib/src/emit/snapshots/plotnik_lib__emit__codegen_tests__comprehensive_multi_definition.snap
+++ b/crates/plotnik-lib/src/emit/snapshots/plotnik_lib__emit__codegen_tests__comprehensive_multi_definition.snap
@@ -75,7 +75,7 @@ Ident:
 
 Expression:
   10   ε                                    11
-  11   ε                                    27, 33
+  11   ε                                    23, 26
 
 Assignment:
   13   ε                                    14
@@ -86,9 +86,5 @@ Assignment:
   20   △                                    21
   21                                        ▶
   22                                        ▶
-  23   ε   [EndEnum]                        22
-  25   !   (number) [Node Set(M1)]          23
-  27   ε   [Enum(M3)]                       25
-  29   ε   [EndEnum]                        22
-  31   !   (identifier) [Node Set(M2)]      29
-  33   ε   [Enum(M4)]                       31
+  23   !   [Enum(M3)] (number) [Node Set(M1) EndEnum]  22
+  26   !   [Enum(M4)] (identifier) [Node Set(M2) EndEnum]  22
diff --git a/crates/plotnik-lib/src/emit/snapshots/plotnik_lib__emit__codegen_tests__definitions_reference.snap b/crates/plotnik-lib/src/emit/snapshots/plotnik_lib__emit__codegen_tests__definitions_reference.snap
index b00392e4..fd993de0 100644
--- a/crates/plotnik-lib/src/emit/snapshots/plotnik_lib__emit__codegen_tests__definitions_reference.snap
+++ b/crates/plotnik-lib/src/emit/snapshots/plotnik_lib__emit__codegen_tests__definitions_reference.snap
@@ -47,7 +47,7 @@ _ObjWrap:
 
 Expression:
   06   ε                                    07
-  07   ε                                    18, 22
+  07   ε                                    16, 19
 
 Root:
   09   ε                                    10
@@ -56,7 +56,5 @@ Root:
   13   △                                    14
   14                                        ▶
   15                                        ▶
-  16   !   (identifier) [Node Set(M0)]      15
-  18   ε   [Null Set(M1)]                   16
-  20   !   (number) [Node Set(M1)]          15
-  22   ε   [Null Set(M0)]                   20
+  16   !   [Null Set(M1)] (identifier) [Node Set(M0)]  15
+  19   !   [Null Set(M0)] (number) [Node Set(M1)]  15
diff --git a/crates/plotnik-lib/src/emit/snapshots/plotnik_lib__emit__codegen_tests__fields_alternation.snap b/crates/plotnik-lib/src/emit/snapshots/plotnik_lib__emit__codegen_tests__fields_alternation.snap
index 703d69b8..a6f8b3cf 100644
--- a/crates/plotnik-lib/src/emit/snapshots/plotnik_lib__emit__codegen_tests__fields_alternation.snap
+++ b/crates/plotnik-lib/src/emit/snapshots/plotnik_lib__emit__codegen_tests__fields_alternation.snap
@@ -46,10 +46,8 @@ Test:
   06   ε                                    07
   07   !   (call_expression)                08
   08   ▽   function: _                      09
-  09   ε                                    14, 18
+  09   ε                                    12, 15
   11                                        ▶
-  12   !   (identifier) [Node Set(M0)]      20
-  14   ε   [Null Set(M1)]                   12
-  16   !   (number) [Node Set(M1)]          20
-  18   ε   [Null Set(M0)]                   16
-  20   △                                    11
+  12   !   [Null Set(M1)] (identifier) [Node Set(M0)]  18
+  15   !   [Null Set(M0)] (number) [Node Set(M1)]  18
+  18   △                                    11
diff --git a/crates/plotnik-lib/src/emit/snapshots/plotnik_lib__emit__codegen_tests__recursion_simple.snap b/crates/plotnik-lib/src/emit/snapshots/plotnik_lib__emit__codegen_tests__recursion_simple.snap
index 39059dd5..b18c7772 100644
--- a/crates/plotnik-lib/src/emit/snapshots/plotnik_lib__emit__codegen_tests__recursion_simple.snap
+++ b/crates/plotnik-lib/src/emit/snapshots/plotnik_lib__emit__codegen_tests__recursion_simple.snap
@@ -56,15 +56,11 @@ _ObjWrap:
 
 Expr:
   06   ε                                    07
-  07   ε                                    17, 25
+  07   ε                                    13, 19
   09   ε   [Set(M2)]                        11
-  11   △                                    19
+  11   △                                    12
   12                                        ▶
-  13   ε   [EndEnum]                        12
-  15   !   (number) [Text Set(M0)]          13
-  17   ε   [Enum(M3)]                       15
-  19   ε   [EndEnum]                        12
-  21   ▷   arguments: (Expr)                06 : 09
-  22   ▽   function: (identifier) [Node Set(M1)]  21
-  24   !   (call_expression)                22
-  25   ε   [Enum(M4)]                       24
+  13   !   [Enum(M3)] (number) [Text Set(M0) EndEnum]  12
+  16   ▷   arguments: (Expr)                06 : 09
+  17   ▽   function: (identifier) [Node Set(M1)]  16
+  19   !   [Enum(M4)] (call_expression) [EndEnum]  17
diff --git a/crates/plotnik-lib/src/emit/snapshots/plotnik_lib__emit__codegen_tests__recursion_with_structured_result.snap b/crates/plotnik-lib/src/emit/snapshots/plotnik_lib__emit__codegen_tests__recursion_with_structured_result.snap
index 4f687d14..27296d13 100644
--- a/crates/plotnik-lib/src/emit/snapshots/plotnik_lib__emit__codegen_tests__recursion_with_structured_result.snap
+++ b/crates/plotnik-lib/src/emit/snapshots/plotnik_lib__emit__codegen_tests__recursion_with_structured_result.snap
@@ -65,7 +65,7 @@ _ObjWrap:
 
 Expr:
   06   ε                                    07
-  07   ε                                    24, 32
+  07   ε                                    20, 26
 
 Test:
   09   ε                                    10
@@ -75,13 +75,9 @@ Test:
   14   △                                    15
   15                                        ▶
   16   ε   [Set(M2)]                        18
-  18   △                                    26
+  18   △                                    19
   19                                        ▶
-  20   ε   [EndEnum]                        19
-  22   !   (number) [Text Set(M0)]          20
-  24   ε   [Enum(M3)]                       22
-  26   ε   [EndEnum]                        19
-  28   ▷   arguments: (Expr)                06 : 16
-  29   ▽   function: (identifier) [Node Set(M1)]  28
-  31   !   (call_expression)                29
-  32   ε   [Enum(M4)]                       31
+  20   !   [Enum(M3)] (number) [Text Set(M0) EndEnum]  19
+  23   ▷   arguments: (Expr)                06 : 16
+  24   ▽   function: (identifier) [Node Set(M1)]  23
+  26   !   [Enum(M4)] (call_expression) [EndEnum]  24
diff --git a/crates/plotnik-lib/src/engine/snapshots/plotnik_lib__engine__engine_tests__recursion_member_chain.snap b/crates/plotnik-lib/src/engine/snapshots/plotnik_lib__engine__engine_tests__recursion_member_chain.snap
index eb0ff868..1a7d06e2 100644
--- a/crates/plotnik-lib/src/engine/snapshots/plotnik_lib__engine__engine_tests__recursion_member_chain.snap
+++ b/crates/plotnik-lib/src/engine/snapshots/plotnik_lib__engine__engine_tests__recursion_member_chain.snap
@@ -7,43 +7,35 @@ Q = (program (expression_statement (Chain) @chain))
 a.b.c
 ---
 {
-  "chain": {
-    "$tag": "Access",
+  "base": {
+    "$tag": "Base",
     "$data": {
-      "base": {
-        "$tag": "Access",
-        "$data": {
-          "base": {
-            "$tag": "Base",
-            "$data": {
-              "name": {
-                "kind": "identifier",
-                "text": "a",
-                "span": [
-                  0,
-                  1
-                ]
-              }
-            }
-          },
-          "prop": {
-            "kind": "property_identifier",
-            "text": "b",
-            "span": [
-              2,
-              3
-            ]
-          }
-        }
-      },
-      "prop": {
-        "kind": "property_identifier",
-        "text": "c",
+      "name": {
+        "kind": "identifier",
+        "text": "a",
         "span": [
-          4,
-          5
+          0,
+          1
         ]
       }
     }
-  }
+  },
+  "prop": {
+    "kind": "property_identifier",
+    "text": "b",
+    "span": [
+      2,
+      3
+    ]
+  },
+  "base": null,
+  "prop": {
+    "kind": "property_identifier",
+    "text": "c",
+    "span": [
+      4,
+      5
+    ]
+  },
+  "chain": null
 }
diff --git a/crates/plotnik-lib/src/engine/snapshots/plotnik_lib__engine__engine_tests__regression_call_searches_for_field_constraint.snap b/crates/plotnik-lib/src/engine/snapshots/plotnik_lib__engine__engine_tests__regression_call_searches_for_field_constraint.snap
index 88cd4d3a..8f28bd42 100644
--- a/crates/plotnik-lib/src/engine/snapshots/plotnik_lib__engine__engine_tests__regression_call_searches_for_field_constraint.snap
+++ b/crates/plotnik-lib/src/engine/snapshots/plotnik_lib__engine__engine_tests__regression_call_searches_for_field_constraint.snap
@@ -7,35 +7,31 @@ Q = (program (expression_statement (Expr) @expr))
 1 + 2
 ---
 {
-  "expr": {
-    "$tag": "Binary",
+  "left": {
+    "$tag": "Lit",
     "$data": {
-      "left": {
-        "$tag": "Lit",
-        "$data": {
-          "val": {
-            "kind": "number",
-            "text": "1",
-            "span": [
-              0,
-              1
-            ]
-          }
-        }
-      },
-      "right": {
-        "$tag": "Lit",
-        "$data": {
-          "val": {
-            "kind": "number",
-            "text": "2",
-            "span": [
-              4,
-              5
-            ]
-          }
-        }
+      "val": {
+        "kind": "number",
+        "text": "1",
+        "span": [
+          0,
+          1
+        ]
       }
     }
-  }
+  },
+  "right": {
+    "$tag": "Lit",
+    "$data": {
+      "val": {
+        "kind": "number",
+        "text": "2",
+        "span": [
+          4,
+          5
+        ]
+      }
+    }
+  },
+  "expr": null
 }