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honey/source/sema/resolve.hon
T

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import "@std/debug"
import "@std/mem"
import "@std/hashmap"
import "@std/arraylist"
import "@source/strpool"
import "@source/ast"
import "@source/diagnostics"
BuiltinType :: enum {
int, float,
bool, string,
void, i64,
f64, usize,
i8, i16, i32, isize,
u8, u16, u32, u64, uint,
anyopaque
c_int, c_uint, c_long, c_ulong, c_longlong, c_ulonglong
c_char, c_uchar, c_short, c_ushort
type
unavailable
}
@hide:file
Builtin :: struct {
name []u8
type BuiltinType
}
@hide:file
builtins [_]Builtin :: [
{ name = "int", type = .int },
{ name = "float", type = .float },
{ name = "bool", type = .bool },
{ name = "string", type = .string },
{ name = "void", type = .void },
{ name = "i64", type = .i64 },
{ name = "f64", type = .f64 },
{ name = "usize", type = .usize },
{ name = "i8", type = .i8 },
{ name = "i16", type = .i16 },
{ name = "i32", type = .i32 },
{ name = "isize", type = .isize },
{ name = "u8", type = .u8 },
{ name = "u16", type = .u16 },
{ name = "u32", type = .u32 },
{ name = "u64", type = .u64 },
{ name = "uint", type = .uint },
{ name = "anyopaque", type = .anyopaque },
{ name = "c_int", type = .c_int },
{ name = "c_uint", type = .c_uint },
{ name = "c_long", type = .c_long },
{ name = "c_ulong", type = .c_ulong },
{ name = "c_longlong", type = .c_longlong },
{ name = "c_ulonglong", type = .c_ulonglong },
{ name = "c_char", type = .c_char },
{ name = "c_schar", type = .c_char },
{ name = "c_uchar", type = .c_uchar },
{ name = "c_short", type = .c_short },
{ name = "c_ushort", type = .c_ushort },
{ name = "c_double", type = .f64 },
{ name = "c_float", type = .unavailable },
{ name = "c_longdouble", type = .unavailable },
{ name = "type", type = .type },
]
@hide:file
intern_builtins proc(
$N usize,
pool @mut strpool.StringPool,
entries @[N]Builtin,
) [N]mut strpool.StringId ! (mem.AllocError | strpool.InternError) {
ids [N]mut strpool.StringId := undefined
for (entries) |builtin, index| ids[index] = try strpool.intern(pool, builtin.name)
return ids
}
BindingKind :: enum { none, declaration, namespace, builtin, invalid }
BindingData :: union {
declaration ast.NodeId
namespace ast.NodeId
builtin BuiltinType
diagnostic diagnostics.DiagnosticId
}
Binding :: struct {
kind BindingKind = .none
data BindingData = BindingData{ diagnostic = diagnostics.no_diagnostic }
}
#! links a file-local import to a package root; failed loads retain their diagnostic.
Import :: struct {
node ast.NodeId
name strpool.StringId
target ?ast.NodeId
diagnostic ?diagnostics.DiagnosticId = null
}
@hide:file
Storage :: struct {
bindings []mut Binding
allocator mem.Allocator
}
#! owns binding storage and retains its allocator; release with deinit.
#! node and diagnostic IDs refer to the caller's Tree and diagnostics.Store.
Resolution :: struct { storage Storage }
@hide:file
Scope :: struct {
names hashmap.AutoHashMap(strpool.StringId, Binding)
parent ?@Scope
}
@hide:file
State :: struct {
tree @ast.Tree
diagnostics @mut diagnostics.Store
bindings []mut Binding
builtin_ids []strpool.StringId
allocator mem.Allocator
namespaces hashmap.AutoHashMap(ast.NodeId, Scope)
aliases []mut ast.NodeId
selections arraylist.ArrayList(ast.NodeId)
}
#! borrows `tree`, its identifier `pool`, and `diagnostic_store` during resolution.
#! `allocator` supplies caller-owned bindings and temporary scopes released before return.
#! release the returned Resolution with deinit, which uses the retained allocator.
resolve proc(
allocator mem.Allocator,
tree @ast.Tree,
pool @mut strpool.StringPool,
diagnostic_store @mut diagnostics.Store,
) Resolution ! (
mem.AllocError
| strpool.InternError
| diagnostics.CapacityError
) {
roots [1]ast.NodeId :: [tree.root]
return try resolve_packages(
allocator,
tree,
roots[..],
&[],
pool,
diagnostic_store,
)
}
#! resolves each package root in its own namespace; AST IDs share the compilation arena.
resolve_packages proc(
allocator mem.Allocator,
tree @ast.Tree,
roots []ast.NodeId,
imports []Import,
pool @mut strpool.StringPool,
diagnostic_store @mut diagnostics.Store,
) Resolution ! (mem.AllocError | strpool.InternError | diagnostics.CapacityError) {
bindings :: try mem.alloc(Binding, allocator, ast.node_count(tree))
errdefer mem.free(allocator, bindings)
mem.set(bindings, Binding{})
builtin_ids :: try intern_builtins(pool, &builtins)
aliases :: try mem.alloc(ast.NodeId, allocator, ast.node_count(tree))
defer mem.free(allocator, aliases)
mem.set(aliases, maxval!(ast.NodeId))
state := State{
tree = tree,
diagnostics = diagnostic_store,
bindings = bindings,
builtin_ids = builtin_ids[..],
allocator = allocator,
namespaces = hashmap.init(allocator),
aliases = aliases,
selections = arraylist.init(allocator),
}
defer arraylist.deinit(&state.selections)
defer {
for (state.namespaces.entries) |entry| {
if (entry.hash == 0) continue
scope := entry.value
hashmap.deinit(&scope.names)
}
hashmap.deinit(&state.namespaces)
}
package_scopes :: try mem.alloc(Scope, allocator, roots.len)
defer mem.free(allocator, package_scopes)
file_scopes :: try mem.alloc(Scope, allocator, ast.source_files(tree).len)
defer mem.free(allocator, file_scopes)
for (file_scopes) |@scope| scope^ = Scope{ names = hashmap.init(allocator), parent = null }
defer { for (file_scopes) |@scope| hashmap.deinit(&scope.names) }
for (roots) |root, index| {
package_scopes[index] = Scope{ names = hashmap.init(allocator), parent = null }
scope := &package_scopes[index]
errdefer hashmap.deinit(&scope.names)
for (0..ast.package_decl_count_at(tree, root)) |i| {
id :: ast.package_decl_at(tree, root, i)
file_scopes[usize(ast.node_span(tree, id).source)].parent = scope
if (ast.file_local(tree, id)) continue
match ast.decl_kind(tree, id) {
.statement: try predeclare(&state, scope, id, ast.statement_decl(tree, id).name)
.function: try predeclare(&state, scope, id, ast.function_decl(tree, id).name)
.import, .invalid: {}
}
}
hashmap.put(&state.namespaces, root, scope^) catch |err| {
match err {
.key_exists: unreachable
else: return err
}
}
}
for (roots) |root| {
for (0..ast.package_decl_count_at(tree, root)) |i| {
id :: ast.package_decl_at(tree, root, i)
if (!ast.file_local(tree, id)) continue
scope :: &file_scopes[usize(ast.node_span(tree, id).source)]
match ast.decl_kind(tree, id) {
.statement: try predeclare(&state, scope, id, ast.statement_decl(tree, id).name)
.function: try predeclare(&state, scope, id, ast.function_decl(tree, id).name)
.import, .invalid: {}
}
}
}
for (imports) |imported| try resolve_import(&state, &file_scopes[usize(ast.node_span(tree, imported.node).source)], imported)
for (roots) |root| try resolve_package(&state, root, file_scopes)
try canonicalize_aliases(&state)
return Resolution{ storage = Storage{
bindings = bindings,
allocator = allocator,
} }
}
@hide:file
resolve_package proc(
state @mut State, root ast.NodeId, file_scopes []Scope,
) void ! (mem.AllocError | diagnostics.CapacityError) {
tree := state.tree^
tree.root = root
for (0..ast.package_decl_count(&tree)) |i| {
id :: ast.package_decl(&tree, i)
scope :: &file_scopes[usize(ast.node_span(&tree, id).source)]
match ast.decl_kind(&tree, id) {
.statement: try resolve_statement_decl(state, scope, id)
.function: try resolve_function(state, scope, id)
.invalid: resolve_invalid(state, id)
.import: {}
}
}
}
@hide:file
resolve_import proc(
state @mut State, scope @mut Scope, imported Import,
) void ! (mem.AllocError | diagnostics.CapacityError) {
span :: ast.import_decl(state.tree, imported.node).span
value := if (imported.diagnostic) |diagnostic|
Binding{ kind = .invalid, data = BindingData{ diagnostic = diagnostic } }
else if (imported.target) |target|
Binding{ kind = .namespace, data = BindingData{ namespace = target } }
else
Binding{ kind = .invalid, data = BindingData{
diagnostic = try diagnostics.add(state.diagnostics, .package_unavailable, span),
} }
if (imported.name == strpool.no_str) {
state.bindings[usize(imported.node)] = value
return
}
if hashmap.get(&scope.names, imported.name) |_| {
state.bindings[usize(imported.node)] = Binding{ kind = .invalid, data = BindingData{
diagnostic = try diagnostics.add(state.diagnostics, .duplicate_name, span),
} }
return
}
if lookup(state, scope.parent, imported.name) |_| {
value = Binding{ kind = .invalid, data = BindingData{
diagnostic = try diagnostics.add(state.diagnostics, .duplicate_name, span),
} }
}
try put_name(scope, imported.name, value)
state.bindings[usize(imported.node)] = value
}
#! releases binding storage with the allocator retained by resolve.
deinit proc(resolution @mut Resolution) void {
mem.free(resolution.storage.allocator, resolution.storage.bindings)
}
binding proc(resolution @Resolution, id ast.NodeId) Binding {
debug.assert(usize(id) < resolution.storage.bindings.len)
return resolution.storage.bindings[usize(id)]
}
#! replaces owned binding storage after AST elaboration; takes ownership of `bindings`.
replace_bindings proc(resolution @mut Resolution, bindings []mut Binding) void {
mem.free(resolution.storage.allocator, resolution.storage.bindings)
resolution.storage.bindings = bindings
}
@hide:file
lookup proc(state @State, scope ?@Scope, name strpool.StringId) ?Binding {
if scope |current| {
if hashmap.get(&current.names, name) |found| return found
return lookup(state, current.parent, name)
}
for (state.builtin_ids) |id, index| {
if (id == name) return Binding{
kind = .builtin,
data = BindingData{ builtin = builtins[index].type },
}
}
return null
}
@hide:file
put_name proc(scope @mut Scope, name strpool.StringId, value Binding) void ! mem.AllocError {
hashmap.put(&scope.names, name, value) catch |err| {
match err {
.key_exists: unreachable
else: return err
}
}
}
@hide:file
predeclare proc(
state @mut State,
scope @mut Scope,
id ast.NodeId,
name_span ast.Span,
) void ! (mem.AllocError | diagnostics.CapacityError) {
name :: ast.name_id(state.tree, id)
if (mem.eql(ast.source_text(state.tree, name_span), "_")) {
state.bindings[usize(id)] = Binding{ kind = .declaration, data = BindingData{ declaration = id } }
return
}
if hashmap.get(&scope.names, name) |_| {
diagnostic :: try diagnostics.add(state.diagnostics, .duplicate_name, name_span)
state.bindings[usize(id)] = Binding{
kind = .invalid,
data = BindingData{ diagnostic = diagnostic },
}
return
}
value := Binding{ kind = .declaration, data = BindingData{ declaration = id } }
if lookup(state, scope.parent, name) |_| {
diagnostic :: try diagnostics.add(state.diagnostics, .duplicate_name, name_span)
# poison the inner name rather than silently binding uses to its ancestor.
value = Binding{ kind = .invalid, data = BindingData{ diagnostic = diagnostic } }
}
try put_name(scope, name, value)
state.bindings[usize(id)] = value
}
@hide:file
resolve_function proc(
state @mut State,
package_scope @Scope,
id ast.NodeId,
) void ! (mem.AllocError | diagnostics.CapacityError) {
tree :: state.tree
function :: ast.function_decl(tree, id)
# compile-time parameters are in scope for subsequent dependent annotations.
signature := Scope{ names = hashmap.init(state.allocator), parent = package_scope }
defer hashmap.deinit(&signature.names)
for (0..ast.function_param_count(tree, id)) |i| {
parameter :: ast.function_param(tree, id, i)
try resolve_expr(state, &signature, ast.param(tree, parameter).type)
if (ast.param(tree, parameter).comptime) try predeclare(state, &signature, parameter, ast.param(tree, parameter).name)
}
try resolve_expr(state, &signature, function.return_type)
scope := Scope{
names = hashmap.init(state.allocator),
parent = package_scope,
}
defer hashmap.deinit(&scope.names)
for (0..ast.function_param_count(tree, id)) |i| {
parameter :: ast.function_param(tree, id, i)
try predeclare(state, &scope, parameter, ast.param(tree, parameter).name)
}
try resolve_block(state, &scope, function.body)
}
@hide:file
resolve_arm proc(state @mut State, parent @Scope, id ast.NodeId) void ! (mem.AllocError | diagnostics.CapacityError) {
scope := Scope{
names = hashmap.init(state.allocator),
parent = parent,
}
defer hashmap.deinit(&scope.names)
try resolve_block(state, &scope, id)
}
@hide:file
resolve_block proc(state @mut State, scope @mut Scope, id ast.NodeId) void ! (mem.AllocError | diagnostics.CapacityError) {
tree :: state.tree
for (0..ast.block_statement_count(tree, id)) |i| {
statement :: ast.block_statement(tree, id, i)
if (ast.stmt_kind(tree, statement) == .declaration) try predeclare(state, scope, statement, ast.statement_decl(tree, statement).name)
}
for (0..ast.block_statement_count(tree, id)) |i| {
statement :: ast.block_statement(tree, id, i)
match ast.stmt_kind(tree, statement) {
.declaration: try resolve_statement_decl(state, scope, statement)
.expression: try resolve_expr(state, scope, ast.statement_expr(tree, statement))
.return_stmt: {
if (ast.return_stmt(tree, statement).value) |value| try resolve_expr(state, scope, value)
}
.yield_stmt: try resolve_expr(state, scope, ast.yield_stmt(tree, statement).value?)
.break_stmt, .continue_stmt: {}
.block_stmt: try resolve_arm(state, scope, ast.statement_block(tree, statement))
.defer_stmt, .errdefer_stmt: {
cleanup :: ast.cleanup_stmt(tree, statement)
try resolve_capture_arm(state, scope, cleanup.body, cleanup.capture)
}
.if_stmt: {
conditional :: ast.if_stmt(tree, statement)
try resolve_expr(state, scope, conditional.condition)
try resolve_capture_arm(state, scope, conditional.then_block, conditional.capture)
if (conditional.else_block) |other| try resolve_arm(state, scope, other)
}
.assignment_stmt: {
assignment :: ast.assignment_stmt(tree, statement)
try resolve_expr(state, scope, assignment.target)
try resolve_expr(state, scope, assignment.value)
}
.while_stmt: {
loop :: ast.while_stmt(tree, statement)
try resolve_expr(state, scope, loop.condition)
try resolve_capture_arm(state, scope, loop.body, loop.capture)
}
.for_stmt: {
loop :: ast.for_stmt(tree, statement)
try resolve_expr(state, scope, loop.iterable)
body_scope := Scope{
names = hashmap.init(state.allocator),
parent = scope,
}
defer hashmap.deinit(&body_scope.names)
if (loop.capture) |capture| try predeclare(state, &body_scope, capture, ast.node_span(tree, capture))
if (loop.index) |index| try predeclare(state, &body_scope, index, ast.node_span(tree, index))
try resolve_block(state, &body_scope, loop.body)
}
.invalid: resolve_invalid(state, statement)
}
}
}
@hide:file
resolve_capture_arm proc(state @mut State, scope @Scope, block ast.NodeId, capture ?ast.NodeId) void ! (mem.AllocError | diagnostics.CapacityError) {
child := Scope{ names = hashmap.init(state.allocator), parent = scope }
defer hashmap.deinit(&child.names)
if (capture) |id| try predeclare(state, &child, id, ast.node_span(state.tree, id))
try resolve_block(state, &child, block)
}
@hide:file
resolve_statement_decl proc(
state @mut State,
scope @Scope,
id ast.NodeId,
) void ! (mem.AllocError | diagnostics.CapacityError) {
declaration :: ast.statement_decl(state.tree, id)
if (ast.expr_kind(state.tree, declaration.initializer) == .alias_expr) state.aliases[usize(id)] = ast.type_operand(state.tree, declaration.initializer)
if (declaration.type) |type| try resolve_expr(state, scope, type)
try resolve_expr(state, scope, declaration.initializer)
}
@hide:file
canonical_binding proc(state @State, original Binding) Binding {
value := original
for (0..(state.aliases.len)) |_| {
if (value.kind != .declaration) break
operand :: state.aliases[usize(value.data.declaration)]
if (operand == maxval!(ast.NodeId)) break
target :: state.bindings[usize(operand)]
if (target.kind == .none) break
if (target.kind == .declaration and target.data.declaration == value.data.declaration) break
value = target
}
return value
}
@hide:file
canonicalize_aliases proc(state @mut State) void ! (mem.AllocError | diagnostics.CapacityError) {
# aliases may forward-reference other aliases or imported namespace members.
for (0..(state.aliases.len)) |_| {
changed := false
for (state.bindings) |@entry| {
value :: canonical_binding(state, entry^)
if (value.kind != entry.kind) changed = true
else if (value.kind == .declaration and value.data.declaration != entry.data.declaration) changed = true
entry^ = value
}
for (state.selections.items) |id| {
expression :: ast.selection_expr(state.tree, id)
base :: state.bindings[usize(expression.base)]
if (base.kind != .namespace or state.bindings[usize(id)].kind != .none) continue
namespace :: hashmap.get(&state.namespaces, base.data.namespace)?
found :: if (ast.expr_kind(state.tree, expression.member) == .identifier)
hashmap.get(&namespace.names, ast.name_id(state.tree, expression.member))
else
null
value :: if (found) |member| canonical_binding(state, member) else Binding{
kind = .invalid,
data = BindingData{ diagnostic = try diagnostics.add(
state.diagnostics, .unknown_name, ast.node_span(state.tree, expression.member),
) },
}
state.bindings[usize(id)] = value
state.bindings[usize(expression.member)] = value
changed = true
}
if (!changed) break
}
}
@hide:file
resolve_invalid proc(state @mut State, id ast.NodeId) void {
if (state.bindings[usize(id)].kind != .none) return
state.bindings[usize(id)] = Binding{
kind = .invalid,
data = BindingData{ diagnostic = ast.invalid(state.tree, id).diagnostic },
}
}
@hide:file
resolve_expr proc(
state @mut State,
scope @Scope,
id ast.NodeId,
) void ! (mem.AllocError | diagnostics.CapacityError) {
# grouped parameters share their type node, including any diagnostic it owns.
if (state.bindings[usize(id)].kind != .none) return
tree :: state.tree
match ast.expr_kind(tree, id) {
.comptime_expr: try resolve_expr(state, scope, ast.comptime_operand(tree, id))
.block_expr: try resolve_arm(state, scope, ast.block_expr(tree, id))
.typed_constant: {
value :: ast.typed_constant(tree, id)
try resolve_expr(state, scope, value.type)
try resolve_expr(state, scope, value.value)
}
.literal_int, .literal_float, .literal_bool, .literal_string, .literal_null, .literal_void,
.literal_undefined: {}
.enum_literal: {}
.distinct_type, .alias_expr, .union_tag_type, .optional_type, .try_expr: try resolve_expr(state, scope, ast.type_operand(tree, id))
.enum_type: {
if (ast.enum_type(tree, id).backing) |backing| try resolve_expr(state, scope, backing)
for (0..ast.enum_member_count(tree, id)) |i| {
member :: ast.field(tree, ast.enum_member(tree, id, i))
if (member.value) |value| try resolve_expr(state, scope, value)
}
}
.match_expr: {
try resolve_expr(state, scope, ast.match_expr(tree, id).subject)
for (0..ast.match_arm_count(tree, id)) |i| {
arm_id :: ast.match_arm(tree, id, i)
arm :: ast.match_arm_view(tree, arm_id)
for (0..ast.match_pattern_count(tree, arm_id)) |j| {
try resolve_expr(state, scope, ast.match_pattern(tree, arm_id, j))
}
arm_scope := Scope{ names = hashmap.init(state.allocator), parent = scope }
defer hashmap.deinit(&arm_scope.names)
if (arm.capture) |capture| try predeclare(state, &arm_scope, capture, ast.node_span(tree, capture))
if (arm.tag_capture) |capture| try predeclare(state, &arm_scope, capture, ast.node_span(tree, capture))
if (arm.expression) try resolve_expr(state, &arm_scope, arm.body)
else try resolve_block(state, &arm_scope, arm.body)
}
}
.catch_expr: {
expression :: ast.catch_expr(tree, id)
try resolve_expr(state, scope, expression.operand)
handler_scope := Scope{ names = hashmap.init(state.allocator), parent = scope }
defer hashmap.deinit(&handler_scope.names)
if (expression.capture) |capture| try predeclare(state, &handler_scope, capture, ast.node_span(tree, capture))
if (expression.handler_is_block) try resolve_block(state, &handler_scope, expression.handler)
else try resolve_expr(state, &handler_scope, expression.handler)
}
.identifier: {
span :: ast.node_span(tree, id)
name :: ast.name_id(tree, id)
if lookup(state, scope, name) |found| {
state.bindings[usize(id)] = found
} else {
diagnostic :: try diagnostics.add(state.diagnostics, .unknown_name, span)
state.bindings[usize(id)] = Binding{
kind = .invalid,
data = BindingData{ diagnostic = diagnostic },
}
}
}
.selection: {
expression :: ast.selection_expr(tree, id)
try arraylist.append(&state.selections, id)
try resolve_expr(state, scope, expression.base)
base :: state.bindings[usize(expression.base)]
value := Binding{}
if (base.kind == .invalid) {
value = base
} else if (base.kind == .namespace) {
namespace :: hashmap.get(&state.namespaces, base.data.namespace)?
found :: if (ast.expr_kind(tree, expression.member) == .identifier)
hashmap.get(&namespace.names, ast.name_id(tree, expression.member))
else
null
if (found) |member| {
value = member
} else {
value = Binding{ kind = .invalid, data = BindingData{
diagnostic = try diagnostics.add(
state.diagnostics,
.unknown_name,
ast.node_span(tree, expression.member),
),
} }
}
}
state.bindings[usize(id)] = value
state.bindings[usize(expression.member)] = value
}
.unary: try resolve_expr(state, scope, ast.unary_expr(tree, id).operand)
.binary, .fallible_type, .sum_type: {
expression :: ast.binary_expr(tree, id)
try resolve_expr(state, scope, expression.left)
try resolve_expr(state, scope, expression.right)
}
.range: {
expression :: ast.range_expr(tree, id)
try resolve_expr(state, scope, expression.start)
try resolve_expr(state, scope, expression.end)
}
.call: {
try resolve_expr(state, scope, ast.call_expr(tree, id).callee)
for (0..ast.call_arg_count(tree, id)) |i| {
try resolve_expr(state, scope, ast.call_arg(tree, id, i))
}
}
.builtin_call: {
for (0..ast.call_arg_count(tree, id)) |i| try resolve_expr(state, scope, ast.call_arg(tree, id, i))
}
.slice: {
expression :: ast.slice_expr(tree, id)
try resolve_expr(state, scope, expression.base)
if (expression.start) |node| try resolve_expr(state, scope, node)
if (expression.end) |node| try resolve_expr(state, scope, node)
if (expression.sentinel) |node| try resolve_expr(state, scope, node)
}
.slice_type: {
type :: ast.slice_type(tree, id)
try resolve_expr(state, scope, type.element)
if (type.sentinel) |node| try resolve_expr(state, scope, node)
}
.pointer_type: try resolve_expr(state, scope, ast.pointer_type(tree, id).element)
.function_type: {
try resolve_expr(state, scope, ast.callable_result(tree, id))
for 0..ast.function_param_count(tree, id) |i| {
parameter :: ast.function_param(tree, id, i)
try resolve_expr(state, scope, ast.param(tree, parameter).type)
}
}
.array_type: {
type :: ast.array_type(tree, id)
if (type.count) |count| try resolve_expr(state, scope, count)
try resolve_expr(state, scope, type.element)
}
.array_literal: {
for (0..ast.array_element_count(tree, id)) |i| {
try resolve_expr(state, scope, ast.array_element(tree, id, i))
}
}
.record_type, .record_literal, .union_type: {
if (ast.expr_kind(tree, id) == .record_literal) {
if (ast.record_literal(tree, id).type) |type| try resolve_expr(state, scope, type)
}
if (ast.expr_kind(tree, id) == .union_type) {
if (ast.union_type(tree, id).tag) |tag| try resolve_expr(state, scope, tag)
}
for (0..ast.record_field_count(tree, id)) |i| {
field :: ast.field(tree, ast.record_field(tree, id, i))
if (field.type) |type| try resolve_expr(state, scope, type)
if (field.value) |value| try resolve_expr(state, scope, value)
}
}
.index: {
expression :: ast.index_expr(tree, id)
try resolve_expr(state, scope, expression.base)
try resolve_expr(state, scope, expression.index)
}
.invalid: resolve_invalid(state, id)
}
}