diff --git a/spicy/toolchain/include/ast/declarations/hook.h b/spicy/toolchain/include/ast/declarations/hook.h
index ffe3e0ac4..44f0bbcb8 100644
--- a/spicy/toolchain/include/ast/declarations/hook.h
+++ b/spicy/toolchain/include/ast/declarations/hook.h
@@ -2,10 +2,7 @@
 
 #pragma once
 
-#include <memory>
-#include <string>
 #include <utility>
-#include <vector>
 
 #include <hilti/ast/expressions/keyword.h>
 #include <hilti/ast/function.h>
@@ -42,12 +39,16 @@ enum class Type {
 
     /** `foreach` hook for containers, executing for each element added. */
     ForEach,
+
+    /** `%error` hook executing when an error has occurred processing the field. */
+    Error,
 };
 
 namespace detail {
 constexpr hilti::util::enum_::Value<Type> Types[] = {
     {Type::Standard, "standard"},
     {Type::ForEach, "foreach"},
+    {Type::Error, "error"},
 };
 
 } // namespace detail
@@ -81,6 +82,8 @@ class Hook : public Declaration {
     hook::Type hookType() const {
         if ( attributes()->has("foreach") )
             return hook::Type::ForEach;
+        else if ( attributes()->has("%error") )
+            return hook::Type::Error;
         else
             return hook::Type::Standard;
     }
diff --git a/spicy/toolchain/include/ast/declarations/unit-hook.h b/spicy/toolchain/include/ast/declarations/unit-hook.h
index aeb60f64c..f61cf826a 100644
--- a/spicy/toolchain/include/ast/declarations/unit-hook.h
+++ b/spicy/toolchain/include/ast/declarations/unit-hook.h
@@ -2,8 +2,6 @@
 
 #pragma once
 
-#include <memory>
-#include <string>
 #include <utility>
 
 #include <hilti/ast/declaration.h>
diff --git a/spicy/toolchain/src/compiler/codegen/codegen.cc b/spicy/toolchain/src/compiler/codegen/codegen.cc
index ec8da5e31..84b5969c6 100644
--- a/spicy/toolchain/src/compiler/codegen/codegen.cc
+++ b/spicy/toolchain/src/compiler/codegen/codegen.cc
@@ -631,6 +631,10 @@ hilti::declaration::Function* CodeGen::compileHook(const type::Unit& unit, const
             builder()->parameter("__dd", field->ddType()->type()->elementType()->type(), hilti::parameter::Kind::In));
         params.push_back(builder()->parameter("__stop", builder()->typeBool(), hilti::parameter::Kind::InOut));
     }
+    else if ( type == declaration::hook::Type::Error ) {
+        if ( params.empty() )
+            params.push_back(builder()->parameter("__excpt", builder()->typeString(), hilti::parameter::Kind::In));
+    }
     else if ( original_field_type ) {
         params.push_back(builder()->parameter("__dd", field->itemType()->type(), hilti::parameter::Kind::In));
 
@@ -652,10 +656,20 @@ hilti::declaration::Function* CodeGen::compileHook(const type::Unit& unit, const
         hid = "__str__";
     }
     else {
+        std::string postfix;
+
+        switch ( type ) {
+            case declaration::hook::Type::Standard: break;
+            case declaration::hook::Type::Error: postfix = "_error"; break;
+            case declaration::hook::Type::ForEach: postfix = "_foreach"; break;
+        }
+
+        hid = fmt("__on_%s%s", id.local(), postfix);
         result = builder()->qualifiedType(builder()->typeVoid(), hilti::Constness::Const);
-        hid = fmt("__on_%s%s", id.local(), (type == declaration::hook::Type::ForEach ? "_foreach" : ""));
     }
 
+    assert(! hid.empty());
+
     if ( ! id.namespace_().empty() )
         hid = fmt("%s::%s", id.namespace_(), hid);
 
diff --git a/spicy/toolchain/src/compiler/codegen/parser-builder.cc b/spicy/toolchain/src/compiler/codegen/parser-builder.cc
index e97bdebf6..45411920f 100644
--- a/spicy/toolchain/src/compiler/codegen/parser-builder.cc
+++ b/spicy/toolchain/src/compiler/codegen/parser-builder.cc
@@ -578,6 +578,24 @@ struct ProductionVisitor : public production::Visitor {
 
         // Parse production
 
+        std::optional<std::pair<std::shared_ptr<Builder>, Builder::TryProxy>> try_;
+
+        if ( is_field_owner ) {
+            bool has_error_hook = false;
+            for ( const auto* h : field->hooks() ) {
+                if ( h->hookType() == declaration::hook::Type::Error )
+                    has_error_hook = true;
+            }
+
+            if ( has_error_hook || ! field->isAnonymous() ) {
+                // Wrap field parsing into try-block for per-field %error hook,
+                // which may be attached directly or provided externally for
+                // named fields.
+                try_ = builder()->addTry();
+                pushBuilder(try_->first);
+            }
+        }
+
         builder()->setLocation(p->location());
 
         Expression* pre_container_offset = nullptr;
@@ -664,6 +682,20 @@ struct ProductionVisitor : public production::Visitor {
             path_tracker.reset();
         }
 
+        if ( try_ ) {
+            popBuilder(); // per-field try-block
+
+            auto catch_ =
+                try_->second.addCatch(builder()->parameter("__except", builder()->typeName("hilti::SystemException")));
+
+            pushBuilder(catch_, [&]() {
+                auto what = builder()->call("hilti::exception_what", {builder()->id("__except")});
+                builder()->addMemberCall(state().self, ID(fmt("__on_%s_error", field->id().local())), {what},
+                                         field->meta());
+                builder()->addRethrow();
+            });
+        }
+
         // Top of stack will now have the final value for the field.
         Expression* stop = builder()->bool_(false);
 
diff --git a/spicy/toolchain/src/compiler/codegen/unit-builder.cc b/spicy/toolchain/src/compiler/codegen/unit-builder.cc
index bbc60fd8f..8c20c08ad 100644
--- a/spicy/toolchain/src/compiler/codegen/unit-builder.cc
+++ b/spicy/toolchain/src/compiler/codegen/unit-builder.cc
@@ -77,6 +77,7 @@ struct FieldBuilder : public visitor::PreOrder {
 
         if ( f->emitHook() ) {
             add_hook_declaration(f, declaration::hook::Type::Standard);
+            add_hook_declaration(f, declaration::hook::Type::Error);
 
             if ( f->isContainer() )
                 add_hook_declaration(f, declaration::hook::Type::ForEach);
diff --git a/spicy/toolchain/src/compiler/parser/parser.yy b/spicy/toolchain/src/compiler/parser/parser.yy
index e7e528bee..f232f242c 100644
--- a/spicy/toolchain/src/compiler/parser/parser.yy
+++ b/spicy/toolchain/src/compiler/parser/parser.yy
@@ -35,7 +35,7 @@ namespace spicy { namespace detail { class Parser; } }
 %verbose
 
 %glr-parser
-%expect 94
+%expect 100
 %expect-rr 168
 
 %{
@@ -902,6 +902,7 @@ unit_hook_attribute
               : FOREACH                          { $$ = builder->attribute("foreach", __loc__); }
               | PRIORITY '=' expr                { $$ = builder->attribute("&priority", std::move($3), __loc__); }
               | PROPERTY                         { $$ = builder->attribute($1, __loc__); }
+              | attribute                        { $$ = std::move($1); }
 
 unit_switch   : SWITCH opt_unit_switch_expr '{' unit_switch_cases '}' opt_attributes opt_unit_field_condition ';'
                                                  { $$ = builder->typeUnitItemSwitch(std::move($2), std::move($4), std::move($7), {}, std::move($6), __loc__); }
diff --git a/spicy/toolchain/src/compiler/resolver.cc b/spicy/toolchain/src/compiler/resolver.cc
index 60ac9996d..1c02758a6 100644
--- a/spicy/toolchain/src/compiler/resolver.cc
+++ b/spicy/toolchain/src/compiler/resolver.cc
@@ -131,9 +131,7 @@ struct VisitorPass2 : visitor::MutatingPostOrder {
     }
 
     void operator()(declaration::UnitHook* n) final {
-        if ( ! n->fullyQualifiedID() ) {
-            if ( auto m = n->parent<hilti::declaration::Module>() )
-                n->setFullyQualifiedID(m->id() + n->id()); // global scope
+        if ( n->hook()->hookType() == declaration::hook::Type::Error ) {
         }
     }
 
diff --git a/spicy/toolchain/src/compiler/validator.cc b/spicy/toolchain/src/compiler/validator.cc
index aa05d9b20..3a790412b 100644
--- a/spicy/toolchain/src/compiler/validator.cc
+++ b/spicy/toolchain/src/compiler/validator.cc
@@ -479,16 +479,22 @@ struct VisitorPost : visitor::PreOrder, hilti::validator::VisitorMixIn {
     }
 
     void operator()(spicy::declaration::Hook* n) final {
-        for ( const auto* attr : n->attributes()->attributes() ) {
-            if ( attr->tag() == "foreach" ) {
+        int count = 0;
+        switch ( n->hookType() ) {
+            case declaration::hook::Type::ForEach:
                 if ( auto field = n->parent<spicy::type::unit::item::Field>(); field && ! field->isContainer() )
                     error("'foreach' can only be used with containers", n);
-            }
-            else if ( attr->tag() == "%debug" || attr->tag() == "&priority" )
-                continue;
-            else
-                error(fmt("unknown hook type '%s'", attr->tag()), n);
+
+                ++count;
+                break;
+
+            case declaration::hook::Type::Error: ++count; break;
+
+            default: break;
         }
+
+        if ( count > 1 )
+            error("hook cannot have be both types, 'foreach' and '%error'", n);
     }
 
     void operator()(spicy::type::unit::item::UnitHook* n) final {
@@ -1018,6 +1024,12 @@ struct VisitorPost : visitor::PreOrder, hilti::validator::VisitorMixIn {
                           id_readable),
                       n, location);
         }
+
+        else if ( hook->hookType() == declaration::hook::Type::Error && ! params.empty() ) {
+            if ( params.size() != 1 || ! hilti::type::same(params[0]->type()->type(), builder()->typeString()) )
+                error("%error hook must only take a string parameter", n, location);
+        }
+
         else {
             if ( auto i = unit->itemByName(ID(id)); ! i )
                 error(fmt("no field '%s' in unit type", id), n, location);
diff --git a/tests/Baseline/spicy.optimization.default-parser-functions/log b/tests/Baseline/spicy.optimization.default-parser-functions/log
index aa9cee054..95f7d4e6e 100644
--- a/tests/Baseline/spicy.optimization.default-parser-functions/log
+++ b/tests/Baseline/spicy.optimization.default-parser-functions/log
@@ -273,6 +273,10 @@
 [debug/optimizer] [<no location>] statement::If "if ( False ) { }" -> null
 [debug/optimizer] [<no location>] statement::If "if ( False ) { }" -> null
 [debug/optimizer] [<no location>] statement::If "if ( False ) { }" -> null
+[debug/optimizer] [<no location>] statement::Try "try { # "<...>/default-parser-functions.spicy:17:8-17:12" # Begin parsing production: Variable: x -> uint<8> spicy_rt::waitForInput(__data, __cur, 1, "expecting 1 bytes for unpacking value", "<...>/default-parser-functions.spicy:17:8-17:12", Null); ((*self).x, __cur) = (*unpack<uint<8>>((__cur, hilti::ByteOrder::Network))); if ( __trim ) (*__data).trim(begin(__cur)); # End parsing production: Variable: x -> uint<8> (*self).__error = __error; __error = (*self).__error; } catch ( hilti::SystemException __except ) { throw; }" -> replacing rethrowing try/catch with just the block
+[debug/optimizer] [<no location>] statement::Try "try { # "<...>/default-parser-functions.spicy:17:8-17:12" # Begin parsing production: Variable: x -> uint<8> spicy_rt::waitForInput(__data, __cur, 1, "expecting 1 bytes for unpacking value", "<...>/default-parser-functions.spicy:17:8-17:12", Null); ((*self).x, __cur) = (*unpack<uint<8>>((__cur, hilti::ByteOrder::Network))); if ( __trim ) (*__data).trim(begin(__cur)); # End parsing production: Variable: x -> uint<8> (*self).__error = __error; __error = (*self).__error; } catch ( hilti::SystemException __except ) { throw; }" -> statement::Block "{ # "<...>/default-parser-functions.spicy:17:8-17:12" # Begin parsing production: Variable: x -> uint<8> spicy_rt::waitForInput(__data, __cur, 1, "expecting 1 bytes for unpacking value", "<...>/default-parser-functions.spicy:17:8-17:12", Null); ((*self).x, __cur) = (*unpack<uint<8>>((__cur, hilti::ByteOrder::Network))); if ( __trim ) (*__data).trim(begin(__cur)); # End parsing production: Variable: x -> uint<8> (*self).__error = __error; __error = (*self).__error; }"
+[debug/optimizer] [<no location>] statement::Try "try { # "<...>/default-parser-functions.spicy:18:8-18:12" # Begin parsing production: Variable: y -> uint<8> spicy_rt::waitForInput(__data, __cur, 1, "expecting 1 bytes for unpacking value", "<...>/default-parser-functions.spicy:18:8-18:12", Null); ((*self).y, __cur) = (*unpack<uint<8>>((__cur, hilti::ByteOrder::Network))); if ( __trim ) (*__data).trim(begin(__cur)); # End parsing production: Variable: y -> uint<8> (*self).__error = __error; (*self).__on_y((*self).y); __error = (*self).__error; } catch ( hilti::SystemException __except ) { throw; }" -> replacing rethrowing try/catch with just the block
+[debug/optimizer] [<no location>] statement::Try "try { # "<...>/default-parser-functions.spicy:18:8-18:12" # Begin parsing production: Variable: y -> uint<8> spicy_rt::waitForInput(__data, __cur, 1, "expecting 1 bytes for unpacking value", "<...>/default-parser-functions.spicy:18:8-18:12", Null); ((*self).y, __cur) = (*unpack<uint<8>>((__cur, hilti::ByteOrder::Network))); if ( __trim ) (*__data).trim(begin(__cur)); # End parsing production: Variable: y -> uint<8> (*self).__error = __error; (*self).__on_y((*self).y); __error = (*self).__error; } catch ( hilti::SystemException __except ) { throw; }" -> statement::Block "{ # "<...>/default-parser-functions.spicy:18:8-18:12" # Begin parsing production: Variable: y -> uint<8> spicy_rt::waitForInput(__data, __cur, 1, "expecting 1 bytes for unpacking value", "<...>/default-parser-functions.spicy:18:8-18:12", Null); ((*self).y, __cur) = (*unpack<uint<8>>((__cur, hilti::ByteOrder::Network))); if ( __trim ) (*__data).trim(begin(__cur)); # End parsing production: Variable: y -> uint<8> (*self).__error = __error; (*self).__on_y((*self).y); __error = (*self).__error; }"
 [debug/optimizer] [<no location>] statement::Try "try { hilti::debugIndent("spicy"); local iterator<stream> __begin = begin(__cur); local strong_ref<stream> filtered = Null; if ( ! filtered ) __result = (*self).__parse_foo__P1_stage2(__data, __begin, __cur, __trim, __lah, __lahe, __error); } catch ( hilti::SystemException __except ) { throw; }" -> replacing rethrowing try/catch with just the block
 [debug/optimizer] [<no location>] statement::Try "try { hilti::debugIndent("spicy"); local iterator<stream> __begin = begin(__cur); local strong_ref<stream> filtered = Null; if ( ! filtered ) __result = (*self).__parse_foo__P1_stage2(__data, __begin, __cur, __trim, __lah, __lahe, __error); } catch ( hilti::SystemException __except ) { throw; }" -> statement::Block "{ hilti::debugIndent("spicy"); local iterator<stream> __begin = begin(__cur); local strong_ref<stream> filtered = Null; if ( ! filtered ) __result = (*self).__parse_foo__P1_stage2(__data, __begin, __cur, __trim, __lah, __lahe, __error); }"
 [debug/optimizer] [default-parser-functions.spicy:10:1-21:2] declaration::Constant "const bool __feat%foo@@P0%supports_filters = False;" -> disabled feature 'supports_filters' of type 'foo::P0' since it is not used
@@ -370,8 +374,14 @@
 [debug/optimizer] [default-parser-functions.spicy:16:18-21:1] statement::Expression "default<void>();" -> removing default<void> statement
 [debug/optimizer] [default-parser-functions.spicy:16:18-21:1] statement::Expression "default<void>();" -> removing default<void> statement
 [debug/optimizer] [default-parser-functions.spicy:17:5-17:13] declaration::Field "hook void __on_x(uint<8> __dd);" -> null
+[debug/optimizer] [default-parser-functions.spicy:17:5-17:13] declaration::Field "hook void __on_x_error(string __excpt);" -> null
 [debug/optimizer] [default-parser-functions.spicy:17:5-17:13] operator_::struct_::MemberCall "(*self).__on_x((*self).x)" -> expression::Ctor "default<void>()" (replacing call to unimplemented method with default value)
+[debug/optimizer] [default-parser-functions.spicy:17:5-17:13] operator_::struct_::MemberCall "(*self).__on_x_error(hilti::exception_what(__except))" -> expression::Ctor "default<void>()" (replacing call to unimplemented method with default value)
 [debug/optimizer] [default-parser-functions.spicy:17:5-17:13] statement::Expression "default<void>();" -> removing default<void> statement
+[debug/optimizer] [default-parser-functions.spicy:17:5-17:13] statement::Expression "default<void>();" -> removing default<void> statement
+[debug/optimizer] [default-parser-functions.spicy:18:5-18:15] declaration::Field "hook void __on_y_error(string __excpt);" -> null
+[debug/optimizer] [default-parser-functions.spicy:18:5-18:15] operator_::struct_::MemberCall "(*self).__on_y_error(hilti::exception_what(__except))" -> expression::Ctor "default<void>()" (replacing call to unimplemented method with default value)
+[debug/optimizer] [default-parser-functions.spicy:18:5-18:15] statement::Expression "default<void>();" -> removing default<void> statement
 [debug/optimizer] [spicy_rt.hlt:28:5-28:76] declaration::Field "method void connect_mime_type(string mime_type, string scope) &internal;" -> null (removing unused member)
 [debug/optimizer] [spicy_rt.hlt:29:5-29:75] declaration::Field "method void connect_mime_type(bytes mime_type, string scope) &internal;" -> null (removing unused member)
 [debug/optimizer] removing field for unused method foo::P0::__on_0x25_confirmed
@@ -416,6 +426,8 @@
 [debug/optimizer] removing field for unused method foo::P2::__on_0x25_synced
 [debug/optimizer] removing field for unused method foo::P2::__on_0x25_undelivered
 [debug/optimizer] removing field for unused method foo::P2::__on_x
+[debug/optimizer] removing field for unused method foo::P2::__on_x_error
+[debug/optimizer] removing field for unused method foo::P2::__on_y_error
 [debug/optimizer] removing field for unused method foo::P2::__str__
 [debug/optimizer] removing field for unused method struct_3::parse1
 [debug/optimizer] removing field for unused method struct_3::parse2
diff --git a/tests/Baseline/spicy.optimization.default-parser-functions/noopt.hlt b/tests/Baseline/spicy.optimization.default-parser-functions/noopt.hlt
index bdc7eeab0..920eade4f 100644
--- a/tests/Baseline/spicy.optimization.default-parser-functions/noopt.hlt
+++ b/tests/Baseline/spicy.optimization.default-parser-functions/noopt.hlt
@@ -72,7 +72,9 @@ public type P2 = struct {
     strong_ref<spicy_rt::Filters> __filters &internal &needed-by-feature="supports_filters";
     optional<hilti::RecoverableFailure> __error &always-emit &internal;
     hook void __on_x(uint<8> __dd);
+    hook void __on_x_error(string __excpt);
     hook void __on_y(uint<8> __dd);
+    hook void __on_y_error(string __excpt);
     hook void __on_0x25_init();
     hook void __on_0x25_done();
     hook void __on_0x25_error(string __except);
@@ -732,33 +734,40 @@ method method tuple<const view<stream>, int<64>, const iterator<stream>, optiona
 method method tuple<const view<stream>, int<64>, const iterator<stream>, optional<hilti::RecoverableFailure>> foo::P2::__parse_foo__P2_stage2(inout value_ref<stream> __data, iterator<stream> __begin, copy view<stream> __cur, copy bool __trim, copy int<64> __lah, copy iterator<stream> __lahe, copy optional<hilti::RecoverableFailure> __error) {
     # "<...>/default-parser-functions.spicy:16:18-21:1"
     local tuple<view<stream>, int<64>, const iterator<stream>, optional<hilti::RecoverableFailure>> __result;
-    # "<...>/default-parser-functions.spicy:17:8-17:12"
+    try {
+        # "<...>/default-parser-functions.spicy:17:8-17:12"
 
-    # Begin parsing production: Variable: x   -> uint<8>
-    spicy_rt::waitForInput(__data, __cur, 1, "expecting 1 bytes for unpacking value", "<...>/default-parser-functions.spicy:17:8-17:12", ::__feat%foo@@P2%supports_filters ? (*self).__filters : Null);
-    ((*self).x, __cur) = (*unpack<uint<8>>((__cur, hilti::ByteOrder::Network)));
+        # Begin parsing production: Variable: x   -> uint<8>
+        spicy_rt::waitForInput(__data, __cur, 1, "expecting 1 bytes for unpacking value", "<...>/default-parser-functions.spicy:17:8-17:12", ::__feat%foo@@P2%supports_filters ? (*self).__filters : Null);
+        ((*self).x, __cur) = (*unpack<uint<8>>((__cur, hilti::ByteOrder::Network)));
 
-    if ( __trim ) 
-        (*__data).trim(begin(__cur));
+        if ( __trim ) 
+            (*__data).trim(begin(__cur));
 
-    # End parsing production: Variable: x   -> uint<8>
+        # End parsing production: Variable: x   -> uint<8>
 
-    (*self).__error = __error;
+        (*self).__error = __error;
 
-    if ( ::__feat%foo@@P2%uses_random_access || ::__feat%foo@@P2%uses_offset ) 
-        (*self).__position_update = Null;
+        if ( ::__feat%foo@@P2%uses_random_access || ::__feat%foo@@P2%uses_offset ) 
+            (*self).__position_update = Null;
 
-    (*self).__on_x((*self).x);
+        (*self).__on_x((*self).x);
 
-    if ( ::__feat%foo@@P2%uses_random_access || ::__feat%foo@@P2%uses_offset ) 
+        if ( ::__feat%foo@@P2%uses_random_access || ::__feat%foo@@P2%uses_offset ) 
 
-        if ( (*self).__position_update ) {
-            __cur = __cur.advance((*(*self).__position_update));
-            (*self).__position_update = Null;
-        }
+            if ( (*self).__position_update ) {
+                __cur = __cur.advance((*(*self).__position_update));
+                (*self).__position_update = Null;
+            }
 
 
-    __error = (*self).__error;
+        __error = (*self).__error;
+    }
+    catch ( hilti::SystemException __except ) {
+        (*self).__on_x_error(hilti::exception_what(__except));
+        throw;
+    }
+
 
     if ( ::__feat%foo@@P2%uses_random_access ) 
         (*self).__begin = __begin;
@@ -767,33 +776,40 @@ method method tuple<const view<stream>, int<64>, const iterator<stream>, optiona
     if ( ::__feat%foo@@P2%uses_offset ) 
         (*self).__offset = cast<uint<64>>(begin(__cur).offset() - __begin.offset());
 
-    # "<...>/default-parser-functions.spicy:18:8-18:12"
+    try {
+        # "<...>/default-parser-functions.spicy:18:8-18:12"
 
-    # Begin parsing production: Variable: y   -> uint<8>
-    spicy_rt::waitForInput(__data, __cur, 1, "expecting 1 bytes for unpacking value", "<...>/default-parser-functions.spicy:18:8-18:12", ::__feat%foo@@P2%supports_filters ? (*self).__filters : Null);
-    ((*self).y, __cur) = (*unpack<uint<8>>((__cur, hilti::ByteOrder::Network)));
+        # Begin parsing production: Variable: y   -> uint<8>
+        spicy_rt::waitForInput(__data, __cur, 1, "expecting 1 bytes for unpacking value", "<...>/default-parser-functions.spicy:18:8-18:12", ::__feat%foo@@P2%supports_filters ? (*self).__filters : Null);
+        ((*self).y, __cur) = (*unpack<uint<8>>((__cur, hilti::ByteOrder::Network)));
 
-    if ( __trim ) 
-        (*__data).trim(begin(__cur));
+        if ( __trim ) 
+            (*__data).trim(begin(__cur));
 
-    # End parsing production: Variable: y   -> uint<8>
+        # End parsing production: Variable: y   -> uint<8>
 
-    (*self).__error = __error;
+        (*self).__error = __error;
 
-    if ( ::__feat%foo@@P2%uses_random_access || ::__feat%foo@@P2%uses_offset ) 
-        (*self).__position_update = Null;
+        if ( ::__feat%foo@@P2%uses_random_access || ::__feat%foo@@P2%uses_offset ) 
+            (*self).__position_update = Null;
 
-    (*self).__on_y((*self).y);
+        (*self).__on_y((*self).y);
 
-    if ( ::__feat%foo@@P2%uses_random_access || ::__feat%foo@@P2%uses_offset ) 
+        if ( ::__feat%foo@@P2%uses_random_access || ::__feat%foo@@P2%uses_offset ) 
 
-        if ( (*self).__position_update ) {
-            __cur = __cur.advance((*(*self).__position_update));
-            (*self).__position_update = Null;
-        }
+            if ( (*self).__position_update ) {
+                __cur = __cur.advance((*(*self).__position_update));
+                (*self).__position_update = Null;
+            }
 
 
-    __error = (*self).__error;
+        __error = (*self).__error;
+    }
+    catch ( hilti::SystemException __except ) {
+        (*self).__on_y_error(hilti::exception_what(__except));
+        throw;
+    }
+
 
     if ( ::__feat%foo@@P2%uses_random_access ) 
         (*self).__begin = __begin;
diff --git a/tests/Baseline/spicy.optimization.default-parser-functions/opt.hlt b/tests/Baseline/spicy.optimization.default-parser-functions/opt.hlt
index 980664ae7..b0ae88da2 100644
--- a/tests/Baseline/spicy.optimization.default-parser-functions/opt.hlt
+++ b/tests/Baseline/spicy.optimization.default-parser-functions/opt.hlt
@@ -170,31 +170,36 @@ method method tuple<const view<stream>, int<64>, const iterator<stream>, optiona
 method method tuple<const view<stream>, int<64>, const iterator<stream>, optional<hilti::RecoverableFailure>> foo::P2::__parse_foo__P2_stage2(inout value_ref<stream> __data, iterator<stream> __begin, copy view<stream> __cur, copy bool __trim, copy int<64> __lah, copy iterator<stream> __lahe, copy optional<hilti::RecoverableFailure> __error) {
     # "<...>/default-parser-functions.spicy:16:18-21:1"
     local tuple<view<stream>, int<64>, const iterator<stream>, optional<hilti::RecoverableFailure>> __result;
-    # "<...>/default-parser-functions.spicy:17:8-17:12"
+    {
+        # "<...>/default-parser-functions.spicy:17:8-17:12"
 
-    # Begin parsing production: Variable: x   -> uint<8>
-    spicy_rt::waitForInput(__data, __cur, 1, "expecting 1 bytes for unpacking value", "<...>/default-parser-functions.spicy:17:8-17:12", Null);
-    ((*self).x, __cur) = (*unpack<uint<8>>((__cur, hilti::ByteOrder::Network)));
+        # Begin parsing production: Variable: x   -> uint<8>
+        spicy_rt::waitForInput(__data, __cur, 1, "expecting 1 bytes for unpacking value", "<...>/default-parser-functions.spicy:17:8-17:12", Null);
+        ((*self).x, __cur) = (*unpack<uint<8>>((__cur, hilti::ByteOrder::Network)));
 
-    if ( __trim ) 
-        (*__data).trim(begin(__cur));
+        if ( __trim ) 
+            (*__data).trim(begin(__cur));
 
-    # End parsing production: Variable: x   -> uint<8>
+        # End parsing production: Variable: x   -> uint<8>
+    }
 
-    # "<...>/default-parser-functions.spicy:18:8-18:12"
+    {
+        # "<...>/default-parser-functions.spicy:18:8-18:12"
 
-    # Begin parsing production: Variable: y   -> uint<8>
-    spicy_rt::waitForInput(__data, __cur, 1, "expecting 1 bytes for unpacking value", "<...>/default-parser-functions.spicy:18:8-18:12", Null);
-    ((*self).y, __cur) = (*unpack<uint<8>>((__cur, hilti::ByteOrder::Network)));
+        # Begin parsing production: Variable: y   -> uint<8>
+        spicy_rt::waitForInput(__data, __cur, 1, "expecting 1 bytes for unpacking value", "<...>/default-parser-functions.spicy:18:8-18:12", Null);
+        ((*self).y, __cur) = (*unpack<uint<8>>((__cur, hilti::ByteOrder::Network)));
 
-    if ( __trim ) 
-        (*__data).trim(begin(__cur));
+        if ( __trim ) 
+            (*__data).trim(begin(__cur));
 
-    # End parsing production: Variable: y   -> uint<8>
+        # End parsing production: Variable: y   -> uint<8>
+
+        (*self).__error = __error;
+        (*self).__on_y((*self).y);
+        __error = (*self).__error;
+    }
 
-    (*self).__error = __error;
-    (*self).__on_y((*self).y);
-    __error = (*self).__error;
     hilti::debugDedent("spicy");
     __result = (__cur, __lah, __lahe, __error);
     return __result;
diff --git a/tests/Baseline/spicy.optimization.unused-types/log b/tests/Baseline/spicy.optimization.unused-types/log
index 1e58b9a6b..ae82b22b6 100644
--- a/tests/Baseline/spicy.optimization.unused-types/log
+++ b/tests/Baseline/spicy.optimization.unused-types/log
@@ -788,6 +788,8 @@
 [debug/optimizer] [<no location>] statement::If "if ( False ) { }" -> null
 [debug/optimizer] [<no location>] statement::If "if ( False ) { }" -> null
 [debug/optimizer] [<no location>] statement::If "if ( False ) { }" -> null
+[debug/optimizer] [<no location>] statement::Try "try { # "<...>/unused-types.spicy:28:14-28:20" # Begin parsing production: Unit: foo__Priv6_2 -> (*self).x = default<const foo::Priv6>(); (__cur, __lah, __lahe, __error) = (*(*self).x).__parse_stage1(__data, __begin, __cur, __trim, __lah, __lahe, __error); # End parsing production: Unit: foo__Priv6_2 -> (*self).__error = __error; __error = (*self).__error; } catch ( hilti::SystemException __except ) { throw; }" -> replacing rethrowing try/catch with just the block
+[debug/optimizer] [<no location>] statement::Try "try { # "<...>/unused-types.spicy:28:14-28:20" # Begin parsing production: Unit: foo__Priv6_2 -> (*self).x = default<const foo::Priv6>(); (__cur, __lah, __lahe, __error) = (*(*self).x).__parse_stage1(__data, __begin, __cur, __trim, __lah, __lahe, __error); # End parsing production: Unit: foo__Priv6_2 -> (*self).__error = __error; __error = (*self).__error; } catch ( hilti::SystemException __except ) { throw; }" -> statement::Block "{ # "<...>/unused-types.spicy:28:14-28:20" # Begin parsing production: Unit: foo__Priv6_2 -> (*self).x = default<const foo::Priv6>(); (__cur, __lah, __lahe, __error) = (*(*self).x).__parse_stage1(__data, __begin, __cur, __trim, __lah, __lahe, __error); # End parsing production: Unit: foo__Priv6_2 -> (*self).__error = __error; __error = (*self).__error; }"
 [debug/optimizer] [<no location>] statement::Try "try { hilti::debugIndent("spicy"); local iterator<stream> __begin = begin(__cur); local strong_ref<stream> filtered = Null; if ( ! filtered ) __result = (*self).__parse_foo__Priv10_stage2(__data, __begin, __cur, __trim, __lah, __lahe, __error); } catch ( hilti::SystemException __except ) { throw; }" -> replacing rethrowing try/catch with just the block
 [debug/optimizer] [<no location>] statement::Try "try { hilti::debugIndent("spicy"); local iterator<stream> __begin = begin(__cur); local strong_ref<stream> filtered = Null; if ( ! filtered ) __result = (*self).__parse_foo__Priv10_stage2(__data, __begin, __cur, __trim, __lah, __lahe, __error); } catch ( hilti::SystemException __except ) { throw; }" -> statement::Block "{ hilti::debugIndent("spicy"); local iterator<stream> __begin = begin(__cur); local strong_ref<stream> filtered = Null; if ( ! filtered ) __result = (*self).__parse_foo__Priv10_stage2(__data, __begin, __cur, __trim, __lah, __lahe, __error); }"
 [debug/optimizer] [<no location>] statement::Try "try { hilti::debugIndent("spicy"); local iterator<stream> __begin = begin(__cur); local strong_ref<stream> filtered = Null; if ( ! filtered ) __result = (*self).__parse_foo__Priv5_stage2(__data, __begin, __cur, __trim, __lah, __lahe, __error); } catch ( hilti::SystemException __except ) { throw; }" -> replacing rethrowing try/catch with just the block
@@ -978,7 +980,7 @@
 [debug/optimizer] [unused-types.spicy:21:14-24:1] declaration::Function "method extern method view<stream> foo::Priv4::parse1(inout value_ref<stream> __data, optional<view<stream>> __cur = Null, optional<spicy_rt::UnitContext> __context) &needed-by-feature="is_filter" &needed-by-feature="supports_sinks" &static { # "<...>/unused-types.spicy:21:14-24:1" local value_ref<foo::Priv4> __unit = value_ref(default<const foo::Priv4>()); local view<stream> __ncur = __cur ? (*__cur) : cast<view<stream>>((*__data)); local int<64> __lahead = 0; local iterator<stream> __lahead_end; local optional<hilti::RecoverableFailure> __error = Null; # "<...>/unused-types.spicy:21:14-24:1" # Begin parsing production: Unit: foo__Priv4 -> Resolved_6 Resolved_7 (__ncur, __lahead, __lahead_end, __error) = (*__unit).__parse_stage1(__data, begin(__ncur), __ncur, True, __lahead, __lahead_end, __error); # End parsing production: Unit: foo__Priv4 -> Resolved_6 Resolved_7 if ( __error ) throw exception("successful synchronization never confirmed: %s" % (hilti::exception_what((*__error)))); return __ncur; }" -> null (removing declaration for unused function)
 [debug/optimizer] [unused-types.spicy:21:14-24:1] declaration::Function "method extern method view<stream> foo::Priv4::parse2(inout value_ref<foo::Priv4> __unit, inout value_ref<stream> __data, optional<view<stream>> __cur = Null, optional<spicy_rt::UnitContext> __context) &needed-by-feature="is_filter" &needed-by-feature="supports_sinks" &static { # "<...>/unused-types.spicy:21:14-24:1" local view<stream> __ncur = __cur ? (*__cur) : cast<view<stream>>((*__data)); local int<64> __lahead = 0; local iterator<stream> __lahead_end; local optional<hilti::RecoverableFailure> __error = Null; # "<...>/unused-types.spicy:21:14-24:1" # Begin parsing production: Unit: foo__Priv4 -> Resolved_6 Resolved_7 (__ncur, __lahead, __lahead_end, __error) = (*__unit).__parse_stage1(__data, begin(__ncur), __ncur, True, __lahead, __lahead_end, __error); # End parsing production: Unit: foo__Priv4 -> Resolved_6 Resolved_7 if ( __error ) throw exception("successful synchronization never confirmed: %s" % (hilti::exception_what((*__error)))); return __ncur; }" -> null (removing declaration for unused function)
 [debug/optimizer] [unused-types.spicy:21:14-24:1] declaration::Function "method extern method view<stream> foo::Priv4::parse3(inout value_ref<spicy_rt::ParsedUnit> __gunit, inout value_ref<stream> __data, optional<view<stream>> __cur = Null, optional<spicy_rt::UnitContext> __context) &needed-by-feature="is_filter" &needed-by-feature="supports_sinks" &static { # "<...>/unused-types.spicy:21:14-24:1" local value_ref<foo::Priv4> __unit = value_ref(default<const foo::Priv4>()); spicy_rt::initializeParsedUnit((*__gunit), __unit, typeinfo(foo::Priv4)); local view<stream> __ncur = __cur ? (*__cur) : cast<view<stream>>((*__data)); local int<64> __lahead = 0; local iterator<stream> __lahead_end; local optional<hilti::RecoverableFailure> __error = Null; # "<...>/unused-types.spicy:21:14-24:1" # Begin parsing production: Unit: foo__Priv4 -> Resolved_6 Resolved_7 (__ncur, __lahead, __lahead_end, __error) = (*__unit).__parse_stage1(__data, begin(__ncur), __ncur, True, __lahead, __lahead_end, __error); # End parsing production: Unit: foo__Priv4 -> Resolved_6 Resolved_7 if ( __error ) throw exception("successful synchronization never confirmed: %s" % (hilti::exception_what((*__error)))); return __ncur; }" -> null (removing declaration for unused function)
-[debug/optimizer] [unused-types.spicy:21:14-24:1] declaration::Function "method method tuple<const view<stream>, int<64>, const iterator<stream>, optional<hilti::RecoverableFailure>> foo::Priv4::__parse_foo__Priv4_stage2(inout value_ref<stream> __data, iterator<stream> __begin, copy view<stream> __cur, copy bool __trim, copy int<64> __lah, copy iterator<stream> __lahe, copy optional<hilti::RecoverableFailure> __error) { # "<...>/unused-types.spicy:21:14-24:1" local tuple<view<stream>, int<64>, const iterator<stream>, optional<hilti::RecoverableFailure>> __result; local value_ref<Priv2> __transient__anon; # "<...>/unused-types.spicy:19:14-19:20" # Begin parsing production: Unit: foo__Priv2_2 -> __transient__anon = default<const foo::Priv2>(); (__cur, __lah, __lahe, __error) = (*__transient__anon).__parse_stage1(__data, __begin, __cur, __trim, __lah, __lahe, __error); # End parsing production: Unit: foo__Priv2_2 -> # "<...>/unused-types.spicy:20:14-20:20" # Begin parsing production: Unit: foo__Priv3_2 -> (*self).x = default<const foo::Priv3>(); (__cur, __lah, __lahe, __error) = (*(*self).x).__parse_stage1(__data, __begin, __cur, __trim, __lah, __lahe, __error); # End parsing production: Unit: foo__Priv3_2 -> (*self).__error = __error; default<void>(); __error = (*self).__error; (*self).__error = __error; default<void>(); __error = (*self).__error; hilti::debugDedent("spicy"); __result = (__cur, __lah, __lahe, __error); return __result; }" -> null (removing declaration for unused function)
+[debug/optimizer] [unused-types.spicy:21:14-24:1] declaration::Function "method method tuple<const view<stream>, int<64>, const iterator<stream>, optional<hilti::RecoverableFailure>> foo::Priv4::__parse_foo__Priv4_stage2(inout value_ref<stream> __data, iterator<stream> __begin, copy view<stream> __cur, copy bool __trim, copy int<64> __lah, copy iterator<stream> __lahe, copy optional<hilti::RecoverableFailure> __error) { # "<...>/unused-types.spicy:21:14-24:1" local tuple<view<stream>, int<64>, const iterator<stream>, optional<hilti::RecoverableFailure>> __result; local value_ref<Priv2> __transient__anon; # "<...>/unused-types.spicy:19:14-19:20" # Begin parsing production: Unit: foo__Priv2_2 -> __transient__anon = default<const foo::Priv2>(); (__cur, __lah, __lahe, __error) = (*__transient__anon).__parse_stage1(__data, __begin, __cur, __trim, __lah, __lahe, __error); # End parsing production: Unit: foo__Priv2_2 -> try { # "<...>/unused-types.spicy:20:14-20:20" # Begin parsing production: Unit: foo__Priv3_2 -> (*self).x = default<const foo::Priv3>(); (__cur, __lah, __lahe, __error) = (*(*self).x).__parse_stage1(__data, __begin, __cur, __trim, __lah, __lahe, __error); # End parsing production: Unit: foo__Priv3_2 -> (*self).__error = __error; default<void>(); __error = (*self).__error; } catch ( hilti::SystemException __except ) { default<void>(); throw; } (*self).__error = __error; default<void>(); __error = (*self).__error; hilti::debugDedent("spicy"); __result = (__cur, __lah, __lahe, __error); return __result; }" -> null (removing declaration for unused function)
 [debug/optimizer] [unused-types.spicy:21:14-24:1] declaration::Function "method method tuple<const view<stream>, int<64>, const iterator<stream>, optional<hilti::RecoverableFailure>> foo::Priv4::__parse_stage1(inout value_ref<stream> __data, iterator<stream> __begin, copy view<stream> __cur, copy bool __trim, copy int<64> __lah, copy iterator<stream> __lahe, copy optional<hilti::RecoverableFailure> __error) { # "<...>/unused-types.spicy:21:14-24:1" local tuple<view<stream>, int<64>, const iterator<stream>, optional<hilti::RecoverableFailure>> __result; try { hilti::debugIndent("spicy"); local iterator<stream> __begin = begin(__cur); (*self).__error = __error; default<void>(); __error = (*self).__error; local strong_ref<stream> filtered = Null; if ( ! filtered ) __result = (*self).__parse_foo__Priv4_stage2(__data, __begin, __cur, __trim, __lah, __lahe, __error); } catch ( hilti::SystemException __except ) { default<void>(); (*self).__error = __error; default<void>(); __error = (*self).__error; throw; } (*self).__error = __error; default<void>(); __error = (*self).__error; return __result; }" -> null (removing declaration for unused function)
 [debug/optimizer] [unused-types.spicy:21:14-24:1] operator_::struct_::MemberCall "(*self).__on_0x25_done()" -> expression::Ctor "default<void>()" (replacing call to unimplemented method with default value)
 [debug/optimizer] [unused-types.spicy:21:14-24:1] operator_::struct_::MemberCall "(*self).__on_0x25_error(hilti::exception_what(__except))" -> expression::Ctor "default<void>()" (replacing call to unimplemented method with default value)
@@ -986,7 +988,9 @@
 [debug/optimizer] [unused-types.spicy:21:14-24:1] operator_::struct_::MemberCall "(*self).__on_0x25_finally()" -> expression::Ctor "default<void>()" (replacing call to unimplemented method with default value)
 [debug/optimizer] [unused-types.spicy:21:14-24:1] operator_::struct_::MemberCall "(*self).__on_0x25_init()" -> expression::Ctor "default<void>()" (replacing call to unimplemented method with default value)
 [debug/optimizer] [unused-types.spicy:23:5-23:13] declaration::Field "hook void __on_x(value_ref<const foo::Priv3> __dd);" -> null
+[debug/optimizer] [unused-types.spicy:23:5-23:13] declaration::Field "hook void __on_x_error(string __excpt);" -> null
 [debug/optimizer] [unused-types.spicy:23:5-23:13] operator_::struct_::MemberCall "(*self).__on_x((*self).x)" -> expression::Ctor "default<void>()" (replacing call to unimplemented method with default value)
+[debug/optimizer] [unused-types.spicy:23:5-23:13] operator_::struct_::MemberCall "(*self).__on_x_error(hilti::exception_what(__except))" -> expression::Ctor "default<void>()" (replacing call to unimplemented method with default value)
 [debug/optimizer] [unused-types.spicy:27:14-27:20] declaration::Field "hook optional<string> __str__();" -> null
 [debug/optimizer] [unused-types.spicy:27:14-27:20] declaration::Field "hook void __on_0x25_confirmed() &needed-by-feature="synchronization";" -> null
 [debug/optimizer] [unused-types.spicy:27:14-27:20] declaration::Field "hook void __on_0x25_done();" -> null
@@ -1066,7 +1070,10 @@
 [debug/optimizer] [unused-types.spicy:29:20-32:1] statement::Expression "default<void>();" -> removing default<void> statement
 [debug/optimizer] [unused-types.spicy:29:20-32:1] statement::Expression "default<void>();" -> removing default<void> statement
 [debug/optimizer] [unused-types.spicy:31:5-31:13] declaration::Field "hook void __on_x(value_ref<const foo::Priv6> __dd);" -> null
+[debug/optimizer] [unused-types.spicy:31:5-31:13] declaration::Field "hook void __on_x_error(string __excpt);" -> null
 [debug/optimizer] [unused-types.spicy:31:5-31:13] operator_::struct_::MemberCall "(*self).__on_x((*self).x)" -> expression::Ctor "default<void>()" (replacing call to unimplemented method with default value)
+[debug/optimizer] [unused-types.spicy:31:5-31:13] operator_::struct_::MemberCall "(*self).__on_x_error(hilti::exception_what(__except))" -> expression::Ctor "default<void>()" (replacing call to unimplemented method with default value)
+[debug/optimizer] [unused-types.spicy:31:5-31:13] statement::Expression "default<void>();" -> removing default<void> statement
 [debug/optimizer] [unused-types.spicy:31:5-31:13] statement::Expression "default<void>();" -> removing default<void> statement
 [debug/optimizer] [unused-types.spicy:35:1-35:30] declaration::Type "type Priv7 = enum { A = 0, B = 1, C = 2 };" -> null (removing unused type)
 [debug/optimizer] [unused-types.spicy:43:22-46:1] declaration::Field "hook optional<string> __str__();" -> null
@@ -1172,6 +1179,7 @@
 [debug/optimizer] removing field for unused method foo::Priv4::__on_0x25_synced
 [debug/optimizer] removing field for unused method foo::Priv4::__on_0x25_undelivered
 [debug/optimizer] removing field for unused method foo::Priv4::__on_x
+[debug/optimizer] removing field for unused method foo::Priv4::__on_x_error
 [debug/optimizer] removing field for unused method foo::Priv4::__parse_stage1
 [debug/optimizer] removing field for unused method foo::Priv4::__str__
 [debug/optimizer] removing field for unused method foo::Priv4::parse1
@@ -1235,6 +1243,7 @@
 [debug/optimizer] removing field for unused method foo::Pub3::__on_0x25_synced
 [debug/optimizer] removing field for unused method foo::Pub3::__on_0x25_undelivered
 [debug/optimizer] removing field for unused method foo::Pub3::__on_x
+[debug/optimizer] removing field for unused method foo::Pub3::__on_x_error
 [debug/optimizer] removing field for unused method foo::Pub3::__str__
 [debug/optimizer] removing field for unused method struct_10::parse1
 [debug/optimizer] removing field for unused method struct_10::parse2
diff --git a/tests/Baseline/spicy.optimization.unused-types/noopt.hlt b/tests/Baseline/spicy.optimization.unused-types/noopt.hlt
index de0b445e6..aaee81bfb 100644
--- a/tests/Baseline/spicy.optimization.unused-types/noopt.hlt
+++ b/tests/Baseline/spicy.optimization.unused-types/noopt.hlt
@@ -128,6 +128,7 @@ type Priv4 = struct {
     strong_ref<spicy_rt::Filters> __filters &internal &needed-by-feature="supports_filters";
     optional<hilti::RecoverableFailure> __error &always-emit &internal;
     hook void __on_x(value_ref<const Priv3> __dd);
+    hook void __on_x_error(string __excpt);
     hook void __on_0x25_init();
     hook void __on_0x25_done();
     hook void __on_0x25_error(string __except);
@@ -215,6 +216,7 @@ public type Pub3 = struct {
     strong_ref<spicy_rt::Filters> __filters &internal &needed-by-feature="supports_filters";
     optional<hilti::RecoverableFailure> __error &always-emit &internal;
     hook void __on_x(value_ref<const Priv6> __dd);
+    hook void __on_x_error(string __excpt);
     hook void __on_0x25_init();
     hook void __on_0x25_done();
     hook void __on_0x25_error(string __except);
@@ -1462,29 +1464,36 @@ method method tuple<const view<stream>, int<64>, const iterator<stream>, optiona
     if ( ::__feat%foo@@Priv4%uses_offset ) 
         (*self).__offset = cast<uint<64>>(begin(__cur).offset() - __begin.offset());
 
-    # "<...>/unused-types.spicy:20:14-20:20"
+    try {
+        # "<...>/unused-types.spicy:20:14-20:20"
 
-    # Begin parsing production: Unit: foo__Priv3_2 ->
-    (*self).x = default<const Priv3>();
-    (__cur, __lah, __lahe, __error) = (*(*self).x).__parse_stage1(__data, __begin, __cur, __trim, __lah, __lahe, __error);
-    # End parsing production: Unit: foo__Priv3_2 ->
+        # Begin parsing production: Unit: foo__Priv3_2 ->
+        (*self).x = default<const Priv3>();
+        (__cur, __lah, __lahe, __error) = (*(*self).x).__parse_stage1(__data, __begin, __cur, __trim, __lah, __lahe, __error);
+        # End parsing production: Unit: foo__Priv3_2 ->
 
-    (*self).__error = __error;
+        (*self).__error = __error;
 
-    if ( ::__feat%foo@@Priv4%uses_random_access || ::__feat%foo@@Priv4%uses_offset ) 
-        (*self).__position_update = Null;
+        if ( ::__feat%foo@@Priv4%uses_random_access || ::__feat%foo@@Priv4%uses_offset ) 
+            (*self).__position_update = Null;
 
-    (*self).__on_x((*self).x);
+        (*self).__on_x((*self).x);
 
-    if ( ::__feat%foo@@Priv4%uses_random_access || ::__feat%foo@@Priv4%uses_offset ) 
+        if ( ::__feat%foo@@Priv4%uses_random_access || ::__feat%foo@@Priv4%uses_offset ) 
 
-        if ( (*self).__position_update ) {
-            __cur = __cur.advance((*(*self).__position_update));
-            (*self).__position_update = Null;
-        }
+            if ( (*self).__position_update ) {
+                __cur = __cur.advance((*(*self).__position_update));
+                (*self).__position_update = Null;
+            }
 
 
-    __error = (*self).__error;
+        __error = (*self).__error;
+    }
+    catch ( hilti::SystemException __except ) {
+        (*self).__on_x_error(hilti::exception_what(__except));
+        throw;
+    }
+
 
     if ( ::__feat%foo@@Priv4%uses_random_access ) 
         (*self).__begin = __begin;
@@ -2246,29 +2255,36 @@ method method tuple<const view<stream>, int<64>, const iterator<stream>, optiona
     if ( ::__feat%foo@@Pub3%uses_offset ) 
         (*self).__offset = cast<uint<64>>(begin(__cur).offset() - __begin.offset());
 
-    # "<...>/unused-types.spicy:28:14-28:20"
+    try {
+        # "<...>/unused-types.spicy:28:14-28:20"
 
-    # Begin parsing production: Unit: foo__Priv6_2 ->
-    (*self).x = default<const Priv6>();
-    (__cur, __lah, __lahe, __error) = (*(*self).x).__parse_stage1(__data, __begin, __cur, __trim, __lah, __lahe, __error);
-    # End parsing production: Unit: foo__Priv6_2 ->
+        # Begin parsing production: Unit: foo__Priv6_2 ->
+        (*self).x = default<const Priv6>();
+        (__cur, __lah, __lahe, __error) = (*(*self).x).__parse_stage1(__data, __begin, __cur, __trim, __lah, __lahe, __error);
+        # End parsing production: Unit: foo__Priv6_2 ->
 
-    (*self).__error = __error;
+        (*self).__error = __error;
 
-    if ( ::__feat%foo@@Pub3%uses_random_access || ::__feat%foo@@Pub3%uses_offset ) 
-        (*self).__position_update = Null;
+        if ( ::__feat%foo@@Pub3%uses_random_access || ::__feat%foo@@Pub3%uses_offset ) 
+            (*self).__position_update = Null;
 
-    (*self).__on_x((*self).x);
+        (*self).__on_x((*self).x);
 
-    if ( ::__feat%foo@@Pub3%uses_random_access || ::__feat%foo@@Pub3%uses_offset ) 
+        if ( ::__feat%foo@@Pub3%uses_random_access || ::__feat%foo@@Pub3%uses_offset ) 
 
-        if ( (*self).__position_update ) {
-            __cur = __cur.advance((*(*self).__position_update));
-            (*self).__position_update = Null;
-        }
+            if ( (*self).__position_update ) {
+                __cur = __cur.advance((*(*self).__position_update));
+                (*self).__position_update = Null;
+            }
 
 
-    __error = (*self).__error;
+        __error = (*self).__error;
+    }
+    catch ( hilti::SystemException __except ) {
+        (*self).__on_x_error(hilti::exception_what(__except));
+        throw;
+    }
+
 
     if ( ::__feat%foo@@Pub3%uses_random_access ) 
         (*self).__begin = __begin;
diff --git a/tests/Baseline/spicy.optimization.unused-types/opt.hlt b/tests/Baseline/spicy.optimization.unused-types/opt.hlt
index 5a2db4ba3..7b44d11ac 100644
--- a/tests/Baseline/spicy.optimization.unused-types/opt.hlt
+++ b/tests/Baseline/spicy.optimization.unused-types/opt.hlt
@@ -306,12 +306,14 @@ method method tuple<const view<stream>, int<64>, const iterator<stream>, optiona
     (__cur, __lah, __lahe, __error) = (*__transient__anon_2).__parse_stage1(__data, __begin, __cur, __trim, __lah, __lahe, __error);
     # End parsing production: Unit: foo__Priv5_2 ->
 
-    # "<...>/unused-types.spicy:28:14-28:20"
+    {
+        # "<...>/unused-types.spicy:28:14-28:20"
 
-    # Begin parsing production: Unit: foo__Priv6_2 ->
-    (*self).x = default<const Priv6>();
-    (__cur, __lah, __lahe, __error) = (*(*self).x).__parse_stage1(__data, __begin, __cur, __trim, __lah, __lahe, __error);
-    # End parsing production: Unit: foo__Priv6_2 ->
+        # Begin parsing production: Unit: foo__Priv6_2 ->
+        (*self).x = default<const Priv6>();
+        (__cur, __lah, __lahe, __error) = (*(*self).x).__parse_stage1(__data, __begin, __cur, __trim, __lah, __lahe, __error);
+        # End parsing production: Unit: foo__Priv6_2 ->
+    }
 
     hilti::debugDedent("spicy");
     __result = (__cur, __lah, __lahe, __error);
diff --git a/tests/Baseline/spicy.types.unit.canonical-ids-with-import/output b/tests/Baseline/spicy.types.unit.canonical-ids-with-import/output
index b51599e8b..8bf47bd96 100644
--- a/tests/Baseline/spicy.types.unit.canonical-ids-with-import/output
+++ b/tests/Baseline/spicy.types.unit.canonical-ids-with-import/output
@@ -420,6 +420,8 @@
 [debug/ast-declarations]           - Field "x" (a::x_3)
 [debug/ast-declarations]           - Field "__on_x" (a::__on_x)
 [debug/ast-declarations]                 - Parameter "__dd" (a::__dd_2)
+[debug/ast-declarations]           - Field "__on_x_error" (a::__on_x_error)
+[debug/ast-declarations]                 - Parameter "__excpt" (a::__excpt)
 [debug/ast-declarations]           - Field "__on_0x25_init" (a::__on_0x25_init)
 [debug/ast-declarations]           - Field "__on_0x25_done" (a::__on_0x25_done)
 [debug/ast-declarations]           - Field "__on_0x25_error" (a::__on_0x25_error)
@@ -513,6 +515,7 @@
 [debug/ast-declarations]             - Parameter "__lahe" (a::__lahe_4)
 [debug/ast-declarations]             - Parameter "__error" (a::__error_5)
 [debug/ast-declarations]             - LocalVariable "__result" (a::__result_2)
+[debug/ast-declarations]               - Parameter "__except" (a::__except_3)
 [debug/ast-declarations]     - Function "a::X::parse1" (a::a::X::parse1)
 [debug/ast-declarations]             - Parameter "__data" (a::__data_8)
 [debug/ast-declarations]             - Parameter "__cur" (a::__cur_8)
diff --git a/tests/Baseline/spicy.types.unit.canonical-ids/output b/tests/Baseline/spicy.types.unit.canonical-ids/output
index 40209046f..99a4d34c5 100644
--- a/tests/Baseline/spicy.types.unit.canonical-ids/output
+++ b/tests/Baseline/spicy.types.unit.canonical-ids/output
@@ -415,6 +415,8 @@
 [debug/ast-declarations]           - Field "ptr" (DNS::ptr_3)
 [debug/ast-declarations]           - Field "__on_ptr" (DNS::__on_ptr)
 [debug/ast-declarations]                 - Parameter "__dd" (DNS::__dd_3)
+[debug/ast-declarations]           - Field "__on_ptr_error" (DNS::__on_ptr_error)
+[debug/ast-declarations]                 - Parameter "__excpt" (DNS::__excpt)
 [debug/ast-declarations]           - Field "__on_0x25_init" (DNS::__on_0x25_init)
 [debug/ast-declarations]           - Field "__on_0x25_done" (DNS::__on_0x25_done)
 [debug/ast-declarations]           - Field "__on_0x25_error" (DNS::__on_0x25_error)
@@ -481,6 +483,8 @@
 [debug/ast-declarations]           - Field "name" (DNS::name_3)
 [debug/ast-declarations]           - Field "__on_name" (DNS::__on_name)
 [debug/ast-declarations]                 - Parameter "__dd" (DNS::__dd_4)
+[debug/ast-declarations]           - Field "__on_name_error" (DNS::__on_name_error)
+[debug/ast-declarations]                 - Parameter "__excpt" (DNS::__excpt_2)
 [debug/ast-declarations]           - Field "__on_0x25_init" (DNS::__on_0x25_init_2)
 [debug/ast-declarations]           - Field "__on_0x25_done" (DNS::__on_0x25_done_2)
 [debug/ast-declarations]           - Field "__on_0x25_error" (DNS::__on_0x25_error_2)
@@ -574,6 +578,7 @@
 [debug/ast-declarations]             - Parameter "__lahe" (DNS::__lahe_6)
 [debug/ast-declarations]             - Parameter "__error" (DNS::__error_8)
 [debug/ast-declarations]             - LocalVariable "__result" (DNS::__result_2)
+[debug/ast-declarations]               - Parameter "__except" (DNS::__except_4)
 [debug/ast-declarations]     - Function "DNS::Label::parse1" (DNS::DNS::Label::parse1)
 [debug/ast-declarations]             - Parameter "__data" (DNS::__data_13)
 [debug/ast-declarations]             - Parameter "__cur" (DNS::__cur_13)
@@ -647,7 +652,7 @@
 [debug/ast-declarations]                     - LocalVariable "__offset1" (DNS::__offset1_2)
 [debug/ast-declarations]                         - LocalVariable "__filtered_data" (DNS::__filtered_data_2)
 [debug/ast-declarations]                         - LocalVariable "__offset2" (DNS::__offset2_2)
-[debug/ast-declarations]               - Parameter "__except" (DNS::__except_4)
+[debug/ast-declarations]               - Parameter "__except" (DNS::__except_5)
 [debug/ast-declarations]     - Function "DNS::Pointer::__parse_DNS__Pointer_2_stage2" (DNS::DNS::Pointer::__parse_DNS__Pointer_2_stage2)
 [debug/ast-declarations]             - Parameter "__data" (DNS::__data_17)
 [debug/ast-declarations]             - Parameter "__begin" (DNS::__begin_12)
@@ -657,6 +662,7 @@
 [debug/ast-declarations]             - Parameter "__lahe" (DNS::__lahe_8)
 [debug/ast-declarations]             - Parameter "__error" (DNS::__error_13)
 [debug/ast-declarations]             - LocalVariable "__result" (DNS::__result_4)
+[debug/ast-declarations]               - Parameter "__except" (DNS::__except_6)
 [debug/ast-declarations]     - Function "DNS::Pointer::parse1" (DNS::DNS::Pointer::parse1)
 [debug/ast-declarations]             - Parameter "__data" (DNS::__data_18)
 [debug/ast-declarations]             - Parameter "__cur" (DNS::__cur_18)
diff --git a/tests/Baseline/spicy.types.unit.error-hook-field-fail/output b/tests/Baseline/spicy.types.unit.error-hook-field-fail/output
new file mode 100644
index 000000000..6b20bfcc8
--- /dev/null
+++ b/tests/Baseline/spicy.types.unit.error-hook-field-fail/output
@@ -0,0 +1,4 @@
+### BTest baseline data generated by btest-diff. Do not edit. Use "btest -U/-u" to update. Requires BTest >= 0.63.
+[error] <...>/error-hook-field-fail.spicy:11:12-12:1: %error hook must only take a string parameter
+[error] <...>/error-hook-field-fail.spicy:14:12-15:1: %error hook must only take a string parameter
+[error] spicyc: aborting after errors
diff --git a/tests/Baseline/spicy.types.unit.error-hook-field/output b/tests/Baseline/spicy.types.unit.error-hook-field/output
new file mode 100644
index 000000000..ee0a2e583
--- /dev/null
+++ b/tests/Baseline/spicy.types.unit.error-hook-field/output
@@ -0,0 +1,29 @@
+### BTest baseline data generated by btest-diff. Do not edit. Use "btest -U/-u" to update. Requires BTest >= 0.63.
+---
+field A standard
+unit %done, [$a=b"A", $b=b"B", $c=b"C"]
+---
+[error] terminating with uncaught exception of type spicy::rt::ParseError: expected bytes literal "B" but input starts with "x" (<...>/error-hook-field.spicy:21:8-21:11)
+field A standard
+field B %error, attached, [$a=b"A", $b=(not set), $c=(not set)]
+field B %error, external, [$a=b"A", $b=(not set), $c=(not set)]
+field B %error, external, expected bytes literal "B" but input starts with "x" (<...>/error-hook-field.spicy:21:8-21:11), [$a=b"A", $b=(not set), $c=(not set)]
+field B %error, inside unit, [$a=b"A", $b=(not set), $c=(not set)]
+field B %error, inside unit, expected bytes literal "B" but input starts with "x" (<...>/error-hook-field.spicy:21:8-21:11), [$a=b"A", $b=(not set), $c=(not set)]
+unit %error, [$a=b"A", $b=(not set), $c=(not set)]
+unit %error, external, expected bytes literal "B" but input starts with "x" (<...>/error-hook-field.spicy:21:8-21:11), [$a=b"A", $b=(not set), $c=(not set)]
+---
+[error] terminating with uncaught exception of type spicy::rt::ParseError: expected bytes literal "C" but input starts with "x" (<...>/error-hook-field.spicy:22:8-22:11)
+field A standard
+unit %error, [$a=b"A", $b=b"B", $c=(not set)]
+unit %error, external, [$a=b"A", $b=b"B", $c=(not set)]
+unit %error, external, expected bytes literal "C" but input starts with "x" (<...>/error-hook-field.spicy:22:8-22:11), [$a=b"A", $b=b"B", $c=(not set)]
+===
+---
+unit %done, [$foo=[$a=b"A", $b=b"B"], $c=b"C"]
+---
+field A %error
+unit %done, [$foo=[$a=(not set), $b=(not set)], $c=b"C"]
+---
+[error] terminating with uncaught exception of type spicy::rt::ParseError: expected bytes literal "B" but input starts with "x" (<...>/error-hook-field.spicy:66:8-66:11)
+unit %error, [$foo=[$a=b"A", $b=(not set)], $c=(not set)]
diff --git a/tests/Baseline/spicy.types.unit.hooks-across-imports/.stderr b/tests/Baseline/spicy.types.unit.hooks-across-imports/.stderr
index 18f4f68c7..9e156c95a 100644
--- a/tests/Baseline/spicy.types.unit.hooks-across-imports/.stderr
+++ b/tests/Baseline/spicy.types.unit.hooks-across-imports/.stderr
@@ -32,39 +32,39 @@
 [debug/ast-stats]     - type::bytes::Iterator: 179
 [debug/ast-stats]     - type::operand_list::Operand: 1257
 [debug/ast-stats]     - type::stream::Iterator: 141
-[debug/ast-stats] garbage collected 8966 nodes in 14 rounds, 21095 left retained
-[debug/ast-stats] garbage collected 2310 nodes in 16 rounds, 24911 left retained
-[debug/ast-stats] garbage collected 2346 nodes in 8 rounds, 26329 left retained
-[debug/ast-stats] garbage collected 4594 nodes in 11 rounds, 27547 left retained
-[debug/ast-stats] garbage collected 412 nodes in 3 rounds, 27547 left retained
+[debug/ast-stats] garbage collected 9044 nodes in 14 rounds, 21359 left retained
+[debug/ast-stats] garbage collected 2418 nodes in 16 rounds, 25283 left retained
+[debug/ast-stats] garbage collected 2346 nodes in 8 rounds, 26701 left retained
+[debug/ast-stats] garbage collected 4762 nodes in 11 rounds, 27919 left retained
+[debug/ast-stats] garbage collected 412 nodes in 3 rounds, 27919 left retained
 [debug/ast-stats] # [HILTI] AST statistics:
 [debug/ast-stats]   - # AST rounds 5
 [debug/ast-stats]   - max tree depth: 27
-[debug/ast-stats]   - # context declarations: 254
+[debug/ast-stats]   - # context declarations: 260
 [debug/ast-stats]   - # context types: 55
 [debug/ast-stats]   - # context modules: 8
-[debug/ast-stats]   - # nodes reachable in AST: 18587
-[debug/ast-stats]   - # nodes live: 27547
-[debug/ast-stats]   - # nodes retained: 27547
+[debug/ast-stats]   - # nodes reachable in AST: 18875
+[debug/ast-stats]   - # nodes live: 27919
+[debug/ast-stats]   - # nodes retained: 27919
 [debug/ast-stats]   - # nodes live > 1%:
 [debug/ast-stats]     - Attribute: 301
-[debug/ast-stats]     - AttributeSet: 765
-[debug/ast-stats]     - QualifiedType: 9116
-[debug/ast-stats]     - declaration::Parameter: 399
-[debug/ast-stats]     - expression::Ctor: 770
-[debug/ast-stats]     - expression::Member: 314
-[debug/ast-stats]     - expression::Name: 992
+[debug/ast-stats]     - AttributeSet: 783
+[debug/ast-stats]     - QualifiedType: 9218
+[debug/ast-stats]     - declaration::Parameter: 411
+[debug/ast-stats]     - expression::Ctor: 782
+[debug/ast-stats]     - expression::Member: 320
+[debug/ast-stats]     - expression::Name: 1010
 [debug/ast-stats]     - type::Bool: 338
-[debug/ast-stats]     - type::Member: 542
-[debug/ast-stats]     - type::Name: 522
-[debug/ast-stats]     - type::OperandList: 798
+[debug/ast-stats]     - type::Member: 554
+[debug/ast-stats]     - type::Name: 534
+[debug/ast-stats]     - type::OperandList: 810
 [debug/ast-stats]     - type::Optional: 465
-[debug/ast-stats]     - type::String: 441
-[debug/ast-stats]     - type::Tuple: 324
+[debug/ast-stats]     - type::String: 465
+[debug/ast-stats]     - type::Tuple: 336
 [debug/ast-stats]     - type::UnsignedInteger: 1695
-[debug/ast-stats]     - type::operand_list::Operand: 1557
+[debug/ast-stats]     - type::operand_list::Operand: 1581
 [debug/ast-stats]     - type::stream::Iterator: 1016
 [debug/ast-stats]     - type::stream::View: 550
-[debug/ast-stats]     - type::tuple::Element: 673
-[debug/ast-stats] garbage collected 32191 nodes in 18 rounds, 0 left retained
+[debug/ast-stats]     - type::tuple::Element: 685
+[debug/ast-stats] garbage collected 32587 nodes in 18 rounds, 0 left retained
 [debug/ast-stats] garbage collected 0 nodes in 1 round, 0 left retained
diff --git a/tests/Baseline/spicy.types.unit.skip-field/skips.txt b/tests/Baseline/spicy.types.unit.skip-field/skips.txt
index 8b8c562ec..01eee0a48 100644
--- a/tests/Baseline/spicy.types.unit.skip-field/skips.txt
+++ b/tests/Baseline/spicy.types.unit.skip-field/skips.txt
@@ -1,9 +1,9 @@
 ### BTest baseline data generated by btest-diff. Do not edit. Use "btest -U/-u" to update. Requires BTest >= 0.63.
-    # Begin parsing production: Skip: a_2 -> skip: a
+        # Begin parsing production: Skip: a_2 -> skip: a
     # Begin parsing production: Skip: _anon_6 -> skip: _anon
-    # Begin parsing production: Skip: c_2 -> skip: c
+        # Begin parsing production: Skip: c_2 -> skip: c
         # Begin parsing production: Skip: _anon_2_2 -> skip: _anon_2
     # Begin parsing production: Skip: _anon_4_2 -> skip: _anon_4
     # Begin parsing production: Skip: _anon_5_2 -> skip: _anon_5
     # Begin parsing production: Skip: _anon_7_2 -> skip: _anon_7
-    # Begin parsing production: Skip: eod_2 -> skip: eod
+        # Begin parsing production: Skip: eod_2 -> skip: eod
diff --git a/tests/Baseline/spicy.types.unit.sub-unit/.stderr b/tests/Baseline/spicy.types.unit.sub-unit/.stderr
index 064693d47..9133b606e 100644
--- a/tests/Baseline/spicy.types.unit.sub-unit/.stderr
+++ b/tests/Baseline/spicy.types.unit.sub-unit/.stderr
@@ -31,40 +31,40 @@
 [debug/ast-stats]     - type::bytes::Iterator: 148
 [debug/ast-stats]     - type::operand_list::Operand: 1257
 [debug/ast-stats]     - type::stream::Iterator: 141
-[debug/ast-stats] garbage collected 5080 nodes in 12 rounds, 17788 left retained
-[debug/ast-stats] garbage collected 2884 nodes in 16 rounds, 20614 left retained
-[debug/ast-stats] garbage collected 1582 nodes in 8 rounds, 21511 left retained
-[debug/ast-stats] garbage collected 3397 nodes in 11 rounds, 22304 left retained
-[debug/ast-stats] garbage collected 286 nodes in 3 rounds, 22304 left retained
+[debug/ast-stats] garbage collected 5119 nodes in 12 rounds, 17920 left retained
+[debug/ast-stats] garbage collected 2938 nodes in 16 rounds, 20800 left retained
+[debug/ast-stats] garbage collected 1582 nodes in 8 rounds, 21697 left retained
+[debug/ast-stats] garbage collected 3481 nodes in 11 rounds, 22490 left retained
+[debug/ast-stats] garbage collected 286 nodes in 3 rounds, 22490 left retained
 [debug/ast-stats] # [HILTI] AST statistics:
 [debug/ast-stats]   - # AST rounds 5
 [debug/ast-stats]   - max tree depth: 27
-[debug/ast-stats]   - # context declarations: 189
+[debug/ast-stats]   - # context declarations: 192
 [debug/ast-stats]   - # context types: 49
 [debug/ast-stats]   - # context modules: 6
-[debug/ast-stats]   - # nodes reachable in AST: 14254
-[debug/ast-stats]   - # nodes live: 22304
-[debug/ast-stats]   - # nodes retained: 22304
+[debug/ast-stats]   - # nodes reachable in AST: 14398
+[debug/ast-stats]   - # nodes live: 22490
+[debug/ast-stats]   - # nodes retained: 22490
 [debug/ast-stats]   - # nodes live > 1%:
 [debug/ast-stats]     - Attribute: 251
-[debug/ast-stats]     - AttributeSet: 593
-[debug/ast-stats]     - QualifiedType: 7347
+[debug/ast-stats]     - AttributeSet: 602
+[debug/ast-stats]     - QualifiedType: 7398
 [debug/ast-stats]     - ctor::String: 290
-[debug/ast-stats]     - declaration::Parameter: 307
-[debug/ast-stats]     - expression::Ctor: 695
-[debug/ast-stats]     - expression::Name: 736
+[debug/ast-stats]     - declaration::Parameter: 313
+[debug/ast-stats]     - expression::Ctor: 701
+[debug/ast-stats]     - expression::Name: 745
 [debug/ast-stats]     - type::Bool: 279
-[debug/ast-stats]     - type::Member: 394
-[debug/ast-stats]     - type::Name: 382
-[debug/ast-stats]     - type::OperandList: 752
+[debug/ast-stats]     - type::Member: 400
+[debug/ast-stats]     - type::Name: 388
+[debug/ast-stats]     - type::OperandList: 758
 [debug/ast-stats]     - type::Optional: 339
-[debug/ast-stats]     - type::String: 536
-[debug/ast-stats]     - type::Tuple: 269
+[debug/ast-stats]     - type::String: 548
+[debug/ast-stats]     - type::Tuple: 275
 [debug/ast-stats]     - type::UnsignedInteger: 1290
-[debug/ast-stats]     - type::Void: 253
-[debug/ast-stats]     - type::operand_list::Operand: 1451
+[debug/ast-stats]     - type::Void: 262
+[debug/ast-stats]     - type::operand_list::Operand: 1463
 [debug/ast-stats]     - type::stream::Iterator: 763
 [debug/ast-stats]     - type::stream::View: 417
-[debug/ast-stats]     - type::tuple::Element: 600
-[debug/ast-stats] garbage collected 23630 nodes in 18 rounds, 0 left retained
+[debug/ast-stats]     - type::tuple::Element: 606
+[debug/ast-stats] garbage collected 23828 nodes in 18 rounds, 0 left retained
 [debug/ast-stats] garbage collected 0 nodes in 1 round, 0 left retained
diff --git a/tests/spicy/types/unit/error-hook-field-fail.spicy b/tests/spicy/types/unit/error-hook-field-fail.spicy
new file mode 100644
index 000000000..c38e00ae7
--- /dev/null
+++ b/tests/spicy/types/unit/error-hook-field-fail.spicy
@@ -0,0 +1,15 @@
+# @TEST-EXEC-FAIL: spicyc -j -d -o test.hlto %INPUT 2>output
+#
+# @TEST-EXEC: btest-diff output
+
+module Mini;
+
+public type Test1 = unit {
+    x: b"X";
+};
+
+on Test1::x(msg: bool) %error { # wrong parameter type
+}
+
+on Test1::x(msg: string, x: bool) %error { # wrong parameter number
+}
diff --git a/tests/spicy/types/unit/error-hook-field.spicy b/tests/spicy/types/unit/error-hook-field.spicy
new file mode 100644
index 000000000..0f9dbfab1
--- /dev/null
+++ b/tests/spicy/types/unit/error-hook-field.spicy
@@ -0,0 +1,67 @@
+# @TEST-EXEC: spicyc -j -d -o test.hlto %INPUT
+#
+# @TEST-EXEC: echo ABC | spicy-driver -p Mini::Test1 test.hlto 2>&1 | sort >>output
+# @TEST-EXEC: echo AxC | (spicy-driver -p Mini::Test1 test.hlto 2>&1; true) | sort >>output
+# @TEST-EXEC: echo ABx | (spicy-driver -p Mini::Test1 test.hlto 2>&1; true) | sort >>output
+#
+# @TEST-EXEC: echo === >>output
+#
+# @TEST-EXEC: echo ABC | spicy-driver -p Mini::Test2 test.hlto 2>&1 | sort >>output
+# @TEST-EXEC: echo C   | spicy-driver -p Mini::Test2 test.hlto 2>&1 | sort >>output
+# @TEST-EXEC: echo AxC | (spicy-driver -p Mini::Test2 test.hlto 2>&1; true) | sort >>output
+#
+# @TEST-EXEC: btest-diff output
+
+module Mini;
+
+public type Test1 = unit {
+    on %init        { print "---"; }
+
+    a: b"A"         { print "field A standard"; }
+    b: b"B"  %error { print "field B %error, attached", self; }
+    c: b"C";
+
+    # TODO: These don't trigger yet
+    on b %error {
+        print "field B %error, inside unit", self;
+    }
+
+    on b(msg: string) %error {
+        print "field B %error, inside unit", msg, self;
+    }
+
+    on %error       { print "unit %error", self; }
+    on %done        { print "unit %done", self; }
+};
+
+on Test1::b %error {
+    print "field B %error, external", self;
+}
+
+on Test1::b(msg: string) %error {
+    print "field B %error, external", msg, self;
+}
+
+on Test1::c %error {
+    print "unit %error, external", self;
+}
+
+on Test1::%error(msg: string) {
+    print "unit %error, external", msg, self;
+}
+
+# Test that backtracks only inside one field's error handler.
+public type Test2 = unit {
+    on %init        { print "---"; }
+
+    foo: Foo &try;
+    c: b"C";
+
+    on %error       { print "unit %error", self; }
+    on %done        { print "unit %done", self; }
+};
+
+type Foo = unit {
+    a: b"A" %error { print "field A %error"; self.backtrack(); }
+    b: b"B";
+};