diff --git a/spec/Exception/TreeExceptionSpec.php b/spec/Exception/TreeExceptionSpec.php
index d059755..1ec7a2c 100644
--- a/spec/Exception/TreeExceptionSpec.php
+++ b/spec/Exception/TreeExceptionSpec.php
@@ -19,12 +19,12 @@ function let()
 
     function it_is_initializable()
     {
-        $this->shouldHaveType(TreeException::CLASS);
+        $this->shouldHaveType(TreeException::class);
     }
 
     function it_is_throwable()
     {
-        $this->shouldHaveType(\Throwable::CLASS);
+        $this->shouldHaveType(\Throwable::class);
     }
 
     function it_contains_error_messages()
diff --git a/spec/MessageRetrieverSpec.php b/spec/MessageRetrieverSpec.php
index a038a07..cb51f78 100644
--- a/spec/MessageRetrieverSpec.php
+++ b/spec/MessageRetrieverSpec.php
@@ -12,7 +12,7 @@ class MessageRetrieverSpec extends ObjectBehavior
 {
     function it_is_initializable()
     {
-        $this->shouldHaveType(MessageRetriever::CLASS);
+        $this->shouldHaveType(MessageRetriever::class);
     }
 
     function it_reads_message_from_single_id()
diff --git a/spec/Money/SignalMoneyFormatterSpec.php b/spec/Money/SignalMoneyFormatterSpec.php
index 2afae36..7e60406 100644
--- a/spec/Money/SignalMoneyFormatterSpec.php
+++ b/spec/Money/SignalMoneyFormatterSpec.php
@@ -15,12 +15,12 @@ class SignalMoneyFormatterSpec extends ObjectBehavior
 {
     function it_is_initializable()
     {
-        $this->shouldHaveType(SignalMoneyFormatter::CLASS);
+        $this->shouldHaveType(SignalMoneyFormatter::class);
     }
 
     function it_is_a_money_formatter()
     {
-        $this->shouldHaveType(MoneyFormatter::CLASS);
+        $this->shouldHaveType(MoneyFormatter::class);
     }
 
     function it_fails_on_non_sek_money()
diff --git a/spec/Money/SignalMoneyParserSpec.php b/spec/Money/SignalMoneyParserSpec.php
index 0e6d05e..5edf05d 100644
--- a/spec/Money/SignalMoneyParserSpec.php
+++ b/spec/Money/SignalMoneyParserSpec.php
@@ -15,12 +15,12 @@ class SignalMoneyParserSpec extends ObjectBehavior
 {
     function it_is_initializable()
     {
-        $this->shouldHaveType(SignalMoneyParser::CLASS);
+        $this->shouldHaveType(SignalMoneyParser::class);
     }
 
     function it_is_a_money_parser()
     {
-        $this->shouldHaveType(MoneyParser::CLASS);
+        $this->shouldHaveType(MoneyParser::class);
     }
 
     function it_fails_on_non_string()
diff --git a/spec/Parser/ParserFactorySpec.php b/spec/Parser/ParserFactorySpec.php
index ae95a51..fad96c6 100644
--- a/spec/Parser/ParserFactorySpec.php
+++ b/spec/Parser/ParserFactorySpec.php
@@ -12,16 +12,16 @@ class ParserFactorySpec extends ObjectBehavior
 {
     function it_is_initializable()
     {
-        $this->shouldHaveType(ParserFactory::CLASS);
+        $this->shouldHaveType(ParserFactory::class);
     }
 
     function it_creates_parsers()
     {
-        $this->createParser()->shouldHaveType(ParserInterface::CLASS);
+        $this->createParser()->shouldHaveType(ParserInterface::class);
     }
 
     function it_creates_parses_with_no_external_visitors()
     {
-        $this->createParser(ParserFactory::VISITOR_IGNORE_OBJECTS)->shouldHaveType(ParserInterface::CLASS);
+        $this->createParser(ParserFactory::VISITOR_IGNORE_OBJECTS)->shouldHaveType(ParserInterface::class);
     }
 }
diff --git a/spec/Parser/ParserSpec.php b/spec/Parser/ParserSpec.php
index 1a657b2..d862cf8 100644
--- a/spec/Parser/ParserSpec.php
+++ b/spec/Parser/ParserSpec.php
@@ -22,12 +22,12 @@ function let(Grammar $grammar, VisitorInterface $visitor)
 
     function it_is_initializable()
     {
-        $this->shouldHaveType(Parser::CLASS);
+        $this->shouldHaveType(Parser::class);
     }
 
     function it_is_a_parser()
     {
-        $this->shouldHaveType(ParserInterface::CLASS);
+        $this->shouldHaveType(ParserInterface::class);
     }
 
     function it_creates_trees($grammar, $visitor, Node $node)
@@ -40,7 +40,7 @@ function it_creates_trees($grammar, $visitor, Node $node)
     function it_throws_parser_exception_if_grammar_fails($grammar)
     {
         $grammar->parse('invalid-ag-file')->willThrow('\InvalidArgumentException');
-        $this->shouldThrow(ParserException::CLASS)->duringParse('invalid-ag-file');
+        $this->shouldThrow(ParserException::class)->duringParse('invalid-ag-file');
     }
 
     function it_converts_to_utf8($grammar, $visitor, Node $node)
diff --git a/spec/Tree/AutogiroFileSpec.php b/spec/Tree/AutogiroFileSpec.php
index 7c3316b..5064d90 100644
--- a/spec/Tree/AutogiroFileSpec.php
+++ b/spec/Tree/AutogiroFileSpec.php
@@ -18,12 +18,12 @@ function let()
 
     function it_is_initializable()
     {
-        $this->shouldHaveType(AutogiroFile::CLASS);
+        $this->shouldHaveType(AutogiroFile::class);
     }
 
     function it_is_a_container_node()
     {
-        $this->shouldHaveType(Container::CLASS);
+        $this->shouldHaveType(Container::class);
     }
 
     function it_contains_a_name()
diff --git a/spec/Tree/ContainerSpec.php b/spec/Tree/ContainerSpec.php
index 9b11a56..2d10db6 100644
--- a/spec/Tree/ContainerSpec.php
+++ b/spec/Tree/ContainerSpec.php
@@ -13,12 +13,12 @@ class ContainerSpec extends ObjectBehavior
 {
     function it_is_initializable()
     {
-        $this->shouldHaveType(Container::CLASS);
+        $this->shouldHaveType(Container::class);
     }
 
     function it_implements_node_interface()
     {
-        $this->shouldHaveType(Node::CLASS);
+        $this->shouldHaveType(Node::class);
     }
 
     function it_contains_a_default_name()
diff --git a/spec/Tree/CountSpec.php b/spec/Tree/CountSpec.php
index b36cd05..246dd58 100644
--- a/spec/Tree/CountSpec.php
+++ b/spec/Tree/CountSpec.php
@@ -22,12 +22,12 @@ function let(Node $count)
 
     function it_is_initializable()
     {
-        $this->shouldHaveType(Count::CLASS);
+        $this->shouldHaveType(Count::class);
     }
 
     function it_is_a_container()
     {
-        $this->shouldHaveType(Container::CLASS);
+        $this->shouldHaveType(Container::class);
     }
 
     function it_contains_a_name()
diff --git a/spec/Tree/DateSpec.php b/spec/Tree/DateSpec.php
index ad45804..4849a40 100644
--- a/spec/Tree/DateSpec.php
+++ b/spec/Tree/DateSpec.php
@@ -12,12 +12,12 @@ class DateSpec extends ObjectBehavior
 {
     function it_is_initializable()
     {
-        $this->shouldHaveType(Date::CLASS);
+        $this->shouldHaveType(Date::class);
     }
 
     function it_implements_node_interface()
     {
-        $this->shouldHaveType(Node::CLASS);
+        $this->shouldHaveType(Node::class);
     }
 
     function it_contains_a_name()
diff --git a/spec/Tree/FlagSpec.php b/spec/Tree/FlagSpec.php
index 475e8bf..991cdac 100644
--- a/spec/Tree/FlagSpec.php
+++ b/spec/Tree/FlagSpec.php
@@ -17,12 +17,12 @@ function let()
 
     function it_is_initializable()
     {
-        $this->shouldHaveType(Flag::CLASS);
+        $this->shouldHaveType(Flag::class);
     }
 
     function it_is_a_node()
     {
-        $this->shouldHaveType(Node::CLASS);
+        $this->shouldHaveType(Node::class);
     }
 
     function it_contains_a_name()
diff --git a/spec/Tree/ImmediateDateSpec.php b/spec/Tree/ImmediateDateSpec.php
index fe917fa..a834b33 100644
--- a/spec/Tree/ImmediateDateSpec.php
+++ b/spec/Tree/ImmediateDateSpec.php
@@ -12,12 +12,12 @@ class ImmediateDateSpec extends ObjectBehavior
 {
     function it_is_initializable()
     {
-        $this->shouldHaveType(ImmediateDate::CLASS);
+        $this->shouldHaveType(ImmediateDate::class);
     }
 
     function it_implements_node_interface()
     {
-        $this->shouldHaveType(Node::CLASS);
+        $this->shouldHaveType(Node::class);
     }
 
     function it_contains_a_name()
diff --git a/spec/Tree/MessageSpec.php b/spec/Tree/MessageSpec.php
index 0027ba5..29daa0c 100644
--- a/spec/Tree/MessageSpec.php
+++ b/spec/Tree/MessageSpec.php
@@ -12,12 +12,12 @@ class MessageSpec extends ObjectBehavior
 {
     function it_is_initializable()
     {
-        $this->shouldHaveType(Message::CLASS);
+        $this->shouldHaveType(Message::class);
     }
 
     function it_is_a_container()
     {
-        $this->shouldHaveType(Container::CLASS);
+        $this->shouldHaveType(Container::class);
     }
 
     function it_contains_a_name()
diff --git a/spec/Tree/NodeSpec.php b/spec/Tree/NodeSpec.php
index 17a21d8..17a4066 100644
--- a/spec/Tree/NodeSpec.php
+++ b/spec/Tree/NodeSpec.php
@@ -13,7 +13,7 @@ class NodeSpec extends ObjectBehavior
 {
     function it_is_initializable()
     {
-        $this->shouldHaveType(Node::CLASS);
+        $this->shouldHaveType(Node::class);
     }
 
     function it_contains_a_name()
@@ -71,7 +71,7 @@ function it_can_have_children(Node $node)
 
     function it_defaults_undefined_child_to_null_node()
     {
-        $this->getChild('this-is-not-definied')->shouldHaveType(NullNode::CLASS);
+        $this->getChild('this-is-not-definied')->shouldHaveType(NullNode::class);
     }
 
     function it_identifies_child_nodes_insensitive_to_case(Node $node)
diff --git a/spec/Tree/NullNodeSpec.php b/spec/Tree/NullNodeSpec.php
index c11a6b1..80609f2 100644
--- a/spec/Tree/NullNodeSpec.php
+++ b/spec/Tree/NullNodeSpec.php
@@ -13,12 +13,12 @@ class NullNodeSpec extends ObjectBehavior
 {
     function it_is_initializable()
     {
-        $this->shouldHaveType(NullNode::CLASS);
+        $this->shouldHaveType(NullNode::class);
     }
 
     function it_implements_node_interface()
     {
-        $this->shouldHaveType(Node::CLASS);
+        $this->shouldHaveType(Node::class);
     }
 
     function it_contains_a_name()
diff --git a/spec/Tree/NumberSpec.php b/spec/Tree/NumberSpec.php
index d961a5e..76e0c10 100644
--- a/spec/Tree/NumberSpec.php
+++ b/spec/Tree/NumberSpec.php
@@ -12,12 +12,12 @@ class NumberSpec extends ObjectBehavior
 {
     function it_is_initializable()
     {
-        $this->shouldHaveType(Number::CLASS);
+        $this->shouldHaveType(Number::class);
     }
 
     function it_implements_node_interface()
     {
-        $this->shouldHaveType(Node::CLASS);
+        $this->shouldHaveType(Node::class);
     }
 
     function it_contains_a_default_name()
diff --git a/spec/Tree/ObjSpec.php b/spec/Tree/ObjSpec.php
index 52345fb..c1aaee9 100644
--- a/spec/Tree/ObjSpec.php
+++ b/spec/Tree/ObjSpec.php
@@ -12,12 +12,12 @@ class ObjSpec extends ObjectBehavior
 {
     function it_is_initializable()
     {
-        $this->shouldHaveType(Obj::CLASS);
+        $this->shouldHaveType(Obj::class);
     }
 
     function it_implements_node_interface()
     {
-        $this->shouldHaveType(Node::CLASS);
+        $this->shouldHaveType(Node::class);
     }
 
     function it_contains_a_default_name()
diff --git a/spec/Tree/RecordSpec.php b/spec/Tree/RecordSpec.php
index 9ebea01..378edc6 100644
--- a/spec/Tree/RecordSpec.php
+++ b/spec/Tree/RecordSpec.php
@@ -17,7 +17,7 @@ function let()
 
     function it_is_initializable()
     {
-        $this->shouldHaveType(Record::CLASS);
+        $this->shouldHaveType(Record::class);
     }
 
     function it_contains_a_name()
diff --git a/spec/Tree/SectionSpec.php b/spec/Tree/SectionSpec.php
index bdf8589..025a33d 100644
--- a/spec/Tree/SectionSpec.php
+++ b/spec/Tree/SectionSpec.php
@@ -21,12 +21,12 @@ function let(Record $nodeA, Record $nodeB)
 
     function it_is_initializable()
     {
-        $this->shouldHaveType(Section::CLASS);
+        $this->shouldHaveType(Section::class);
     }
 
     function it_is_a_container()
     {
-        $this->shouldHaveType(Container::CLASS);
+        $this->shouldHaveType(Container::class);
     }
 
     function it_contains_a_name()
diff --git a/spec/Tree/SummarySpec.php b/spec/Tree/SummarySpec.php
index 13388d8..0df5b6c 100644
--- a/spec/Tree/SummarySpec.php
+++ b/spec/Tree/SummarySpec.php
@@ -22,12 +22,12 @@ function let(Node $amount)
 
     function it_is_initializable()
     {
-        $this->shouldHaveType(Summary::CLASS);
+        $this->shouldHaveType(Summary::class);
     }
 
     function it_is_a_container()
     {
-        $this->shouldHaveType(Container::CLASS);
+        $this->shouldHaveType(Container::class);
     }
 
     function it_contains_a_name()
diff --git a/spec/Tree/TextSpec.php b/spec/Tree/TextSpec.php
index dffef50..544f49b 100644
--- a/spec/Tree/TextSpec.php
+++ b/spec/Tree/TextSpec.php
@@ -12,12 +12,12 @@ class TextSpec extends ObjectBehavior
 {
     function it_is_initializable()
     {
-        $this->shouldHaveType(Text::CLASS);
+        $this->shouldHaveType(Text::class);
     }
 
     function it_implements_node_interface()
     {
-        $this->shouldHaveType(Node::CLASS);
+        $this->shouldHaveType(Node::class);
     }
 
     function it_contains_a_default_name()
diff --git a/spec/Visitor/AccountVisitorSpec.php b/spec/Visitor/AccountVisitorSpec.php
index 2696661..3a94133 100644
--- a/spec/Visitor/AccountVisitorSpec.php
+++ b/spec/Visitor/AccountVisitorSpec.php
@@ -27,7 +27,7 @@ function let(
 
     function it_is_initializable()
     {
-        $this->shouldHaveType(AccountVisitor::CLASS);
+        $this->shouldHaveType(AccountVisitor::class);
     }
 
     function it_fails_on_unvalid_account_number(Node $node, $accountFactory, $errorObj)
@@ -36,7 +36,7 @@ function it_fails_on_unvalid_account_number(Node $node, $accountFactory, $errorO
         $node->hasChild(Node::OBJ)->willReturn(false);
 
         $node->getValueFrom(Node::NUMBER)->willReturn('not-valid');
-        $accountFactory->createAccount('not-valid')->willThrow(BankingException::CLASS);
+        $accountFactory->createAccount('not-valid')->willThrow(BankingException::class);
 
         $this->beforeAccount($node);
         $errorObj->addError(Argument::type('string'), Argument::cetera())->shouldHaveBeenCalledTimes(1);
@@ -81,7 +81,7 @@ function it_fails_on_unvalid_bankgiro_number(Node $node, $bankgiroFactory, $erro
         $node->hasChild(Node::OBJ)->willReturn(false);
 
         $node->getValueFrom(Node::NUMBER)->willReturn('not-valid');
-        $bankgiroFactory->createAccount('not-valid')->willThrow(BankingException::CLASS);
+        $bankgiroFactory->createAccount('not-valid')->willThrow(BankingException::class);
 
         $this->beforePayeeBankgiro($node);
         $errorObj->addError(Argument::type('string'), Argument::cetera())->shouldHaveBeenCalledTimes(1);
diff --git a/spec/Visitor/AmountVisitorSpec.php b/spec/Visitor/AmountVisitorSpec.php
index e5708ac..ff09989 100644
--- a/spec/Visitor/AmountVisitorSpec.php
+++ b/spec/Visitor/AmountVisitorSpec.php
@@ -22,7 +22,7 @@ function let(ErrorObject $errorObj, MoneyParser $moneyParser)
 
     function it_is_initializable()
     {
-        $this->shouldHaveType(AmountVisitor::CLASS);
+        $this->shouldHaveType(AmountVisitor::class);
     }
 
     function it_does_not_create_amount_if_object_exists(Node $node)
diff --git a/spec/Visitor/CountingVisitorSpec.php b/spec/Visitor/CountingVisitorSpec.php
index 01e08d7..2e7ce0d 100644
--- a/spec/Visitor/CountingVisitorSpec.php
+++ b/spec/Visitor/CountingVisitorSpec.php
@@ -19,7 +19,7 @@ function let(ErrorObject $errorObj)
 
     function it_is_initializable()
     {
-        $this->shouldHaveType(CountingVisitor::CLASS);
+        $this->shouldHaveType(CountingVisitor::class);
     }
 
     function it_validates_record_counts(Node $count, Node $record, $errorObj)
diff --git a/spec/Visitor/DateVisitorSpec.php b/spec/Visitor/DateVisitorSpec.php
index 5c55429..866423e 100644
--- a/spec/Visitor/DateVisitorSpec.php
+++ b/spec/Visitor/DateVisitorSpec.php
@@ -20,7 +20,7 @@ function let(ErrorObject $errorObj)
 
     function it_is_initializable()
     {
-        $this->shouldHaveType(DateVisitor::CLASS);
+        $this->shouldHaveType(DateVisitor::class);
     }
 
     function it_does_not_create_if_date_object_exists(Node $node)
diff --git a/spec/Visitor/ErrorObjectSpec.php b/spec/Visitor/ErrorObjectSpec.php
index 7780876..5abd524 100644
--- a/spec/Visitor/ErrorObjectSpec.php
+++ b/spec/Visitor/ErrorObjectSpec.php
@@ -11,7 +11,7 @@ class ErrorObjectSpec extends ObjectBehavior
 {
     function it_is_initializable()
     {
-        $this->shouldHaveType(ErrorObject::CLASS);
+        $this->shouldHaveType(ErrorObject::class);
     }
 
     function it_defaults_to_no_error()
diff --git a/spec/Visitor/MessageVisitorSpec.php b/spec/Visitor/MessageVisitorSpec.php
index 1450253..55e6a62 100644
--- a/spec/Visitor/MessageVisitorSpec.php
+++ b/spec/Visitor/MessageVisitorSpec.php
@@ -21,7 +21,7 @@ function let(ErrorObject $errorObj, MessageRetriever $messages)
 
     function it_is_initializable()
     {
-        $this->shouldHaveType(MessageVisitor::CLASS);
+        $this->shouldHaveType(MessageVisitor::class);
     }
 
     function it_fails_on_unvalid_message(Node $file, Node $record, Node $msg, $errorObj, $messages)
diff --git a/spec/Visitor/NumberVisitorSpec.php b/spec/Visitor/NumberVisitorSpec.php
index 293c5b7..9b8e7c4 100644
--- a/spec/Visitor/NumberVisitorSpec.php
+++ b/spec/Visitor/NumberVisitorSpec.php
@@ -19,7 +19,7 @@ function let(ErrorObject $errorObj)
 
     function it_is_initializable()
     {
-        $this->shouldHaveType(NumberVisitor::CLASS);
+        $this->shouldHaveType(NumberVisitor::class);
     }
 
     function it_captures_invalid_nodes(Number $node, $errorObj)
diff --git a/spec/Visitor/PayeeVisitorSpec.php b/spec/Visitor/PayeeVisitorSpec.php
index 0d8d8ff..1a43bba 100644
--- a/spec/Visitor/PayeeVisitorSpec.php
+++ b/spec/Visitor/PayeeVisitorSpec.php
@@ -14,7 +14,7 @@ class PayeeVisitorSpec extends ObjectBehavior
 {
     function it_is_initializable()
     {
-        $this->shouldHaveType(PayeeVisitor::CLASS);
+        $this->shouldHaveType(PayeeVisitor::class);
     }
 
     function let(
diff --git a/spec/Visitor/PaymentVisitorSpec.php b/spec/Visitor/PaymentVisitorSpec.php
index 886398f..a312e7e 100644
--- a/spec/Visitor/PaymentVisitorSpec.php
+++ b/spec/Visitor/PaymentVisitorSpec.php
@@ -20,7 +20,7 @@ function let(ErrorObject $errorObj)
 
     function it_is_initializable()
     {
-        $this->shouldHaveType(PaymentVisitor::CLASS);
+        $this->shouldHaveType(PaymentVisitor::class);
     }
 
     function it_fails_if_interval_is_used_with_immediate_date_in_incoming_payment(
diff --git a/spec/Visitor/StateIdVisitorSpec.php b/spec/Visitor/StateIdVisitorSpec.php
index 7573dd0..cc7c10e 100644
--- a/spec/Visitor/StateIdVisitorSpec.php
+++ b/spec/Visitor/StateIdVisitorSpec.php
@@ -27,7 +27,7 @@ function let(
 
     function it_is_initializable()
     {
-        $this->shouldHaveType(StateIdVisitor::CLASS);
+        $this->shouldHaveType(StateIdVisitor::class);
     }
 
     function it_does_not_create_id_if_object_is_set(Node $node)
@@ -51,7 +51,7 @@ function it_fails_on_unvalid_organizational_id(Node $node, $organizationIdFactor
         $node->hasChild(Node::OBJ)->willReturn(false);
 
         $node->getValueFrom(Node::NUMBER)->willReturn('99-not-a-valid-id');
-        $organizationIdFactory->createId('-not-a-valid-id')->willThrow(IdException::CLASS);
+        $organizationIdFactory->createId('-not-a-valid-id')->willThrow(IdException::class);
 
         $this->beforeStateId($node);
         $errorObj->addError(Argument::type('string'), Argument::cetera())->shouldHaveBeenCalledTimes(1);
@@ -78,7 +78,7 @@ function it_fails_on_unvalid_personal_id(Node $node, $personalIdFactory, $errorO
         $node->hasChild(Node::OBJ)->willReturn(false);
 
         $node->getValueFrom(Node::NUMBER)->willReturn('not-valid');
-        $personalIdFactory->createId('not-valid')->willThrow(IdException::CLASS);
+        $personalIdFactory->createId('not-valid')->willThrow(IdException::class);
 
         $this->beforeStateId($node);
         $errorObj->addError(Argument::type('string'), Argument::cetera())->shouldHaveBeenCalledTimes(1);
diff --git a/spec/Visitor/SummaryVisitorSpec.php b/spec/Visitor/SummaryVisitorSpec.php
index 79d6ce8..fdeabf4 100644
--- a/spec/Visitor/SummaryVisitorSpec.php
+++ b/spec/Visitor/SummaryVisitorSpec.php
@@ -20,7 +20,7 @@ function let(ErrorObject $errorObj)
 
     function it_is_initializable()
     {
-        $this->shouldHaveType(SummaryVisitor::CLASS);
+        $this->shouldHaveType(SummaryVisitor::class);
     }
 
     function it_validates_summary(
diff --git a/spec/Visitor/TextVisitorSpec.php b/spec/Visitor/TextVisitorSpec.php
index cf258ea..862e5e0 100644
--- a/spec/Visitor/TextVisitorSpec.php
+++ b/spec/Visitor/TextVisitorSpec.php
@@ -19,7 +19,7 @@ function let(ErrorObject $errorObj)
 
     function it_is_initializable()
     {
-        $this->shouldHaveType(TextVisitor::CLASS);
+        $this->shouldHaveType(TextVisitor::class);
     }
 
     function it_captures_invalid_text_nodes(Text $textNode, $errorObj)
diff --git a/spec/Visitor/VisitorContainerSpec.php b/spec/Visitor/VisitorContainerSpec.php
index 488b71f..9a6a68f 100644
--- a/spec/Visitor/VisitorContainerSpec.php
+++ b/spec/Visitor/VisitorContainerSpec.php
@@ -21,7 +21,7 @@ function let(ErrorObject $errorObj)
 
     function it_is_initializable()
     {
-        $this->shouldHaveType(VisitorContainer::CLASS);
+        $this->shouldHaveType(VisitorContainer::class);
     }
 
     function it_can_load_visitors(VisitorInterface $visitorA, VisitorInterface $visitorB)
@@ -59,7 +59,7 @@ function it_throws_exception_on_errors($errorObj, Node $node)
         $node->getType()->willReturn('');
         $errorObj->hasErrors()->willReturn(true);
         $errorObj->getErrors()->willReturn(['an error']);
-        $this->shouldThrow(TreeException::CLASS)->duringVisitAfter($node);
+        $this->shouldThrow(TreeException::class)->duringVisitAfter($node);
     }
 
     function it_resets_errors($errorObj, Node $node)
diff --git a/spec/Visitor/VisitorFactorySpec.php b/spec/Visitor/VisitorFactorySpec.php
index 5ff8826..b70de1d 100644
--- a/spec/Visitor/VisitorFactorySpec.php
+++ b/spec/Visitor/VisitorFactorySpec.php
@@ -13,12 +13,12 @@ class VisitorFactorySpec extends ObjectBehavior
 {
     function it_is_initializable()
     {
-        $this->shouldHaveType(VisitorFactory::CLASS);
+        $this->shouldHaveType(VisitorFactory::class);
     }
 
     function it_creates_visitors()
     {
-        $this->createVisitors()->shouldHaveType(VisitorInterface::CLASS);
+        $this->createVisitors()->shouldHaveType(VisitorInterface::class);
     }
 
     function it_creates_visitors_with_no_external_visitors()
diff --git a/spec/Visitor/VisitorSpec.php b/spec/Visitor/VisitorSpec.php
index e85796d..f592292 100644
--- a/spec/Visitor/VisitorSpec.php
+++ b/spec/Visitor/VisitorSpec.php
@@ -12,7 +12,7 @@ class VisitorSpec extends ObjectBehavior
 {
     function it_is_initializable()
     {
-        $this->shouldHaveType(Visitor::CLASS);
+        $this->shouldHaveType(Visitor::class);
     }
 
     function it_ignores_unknown_nodes(Node $node)
diff --git a/spec/Writer/OutputSpec.php b/spec/Writer/OutputSpec.php
index 3a125e7..dc7cb9a 100644
--- a/spec/Writer/OutputSpec.php
+++ b/spec/Writer/OutputSpec.php
@@ -12,7 +12,7 @@ class OutputSpec extends ObjectBehavior
 {
     function it_is_initializable()
     {
-        $this->shouldHaveType(Output::CLASS);
+        $this->shouldHaveType(Output::class);
     }
 
     function it_captures_output()
diff --git a/spec/Writer/PrintingVisitorSpec.php b/spec/Writer/PrintingVisitorSpec.php
index cf204b8..5f96581 100644
--- a/spec/Writer/PrintingVisitorSpec.php
+++ b/spec/Writer/PrintingVisitorSpec.php
@@ -27,12 +27,12 @@ function let(MoneyFormatter $moneyFormatter, Output $output)
 
     function it_is_initializable()
     {
-        $this->shouldHaveType(PrintingVisitor::CLASS);
+        $this->shouldHaveType(PrintingVisitor::class);
     }
 
     function it_is_a_visitor()
     {
-        $this->shouldHaveType(Visitor::CLASS);
+        $this->shouldHaveType(Visitor::class);
     }
 
     function it_prints_dates(Node $node, $output)
@@ -119,7 +119,7 @@ function it_prints_intervals(Node $node, $output)
     function it_fails_on_invalid_intervals(Node $node, $output)
     {
         $node->getValue()->willReturn('9');
-        $this->shouldThrow(RuntimeException::CLASS)->duringBeforeInterval($node);
+        $this->shouldThrow(RuntimeException::class)->duringBeforeInterval($node);
         $output->write(Argument::any())->shouldNotHaveBeenCalled();
     }
 
@@ -147,7 +147,7 @@ function it_pads_repititions(Node $node, $output)
     function it_fails_on_invalid_repititions(Node $node, $output)
     {
         $node->getValue()->willReturn('1000');
-        $this->shouldThrow(RuntimeException::CLASS)->duringBeforeRepetitions($node);
+        $this->shouldThrow(RuntimeException::class)->duringBeforeRepetitions($node);
         $output->write(Argument::any())->shouldNotHaveBeenCalled();
     }
 
@@ -169,13 +169,13 @@ function it_fails_on_non_sek_amounts(Node $node)
     function it_fails_on_to_large_amounts(Node $node)
     {
         $node->getValue()->willReturn(Money::SEK('1000000000000'));
-        $this->shouldThrow(RuntimeException::CLASS)->duringBeforeAmount($node);
+        $this->shouldThrow(RuntimeException::class)->duringBeforeAmount($node);
     }
 
     function it_fails_on_to_small_amounts(Node $node)
     {
         $node->getValue()->willReturn(Money::SEK('-1000000000000'));
-        $this->shouldThrow(RuntimeException::CLASS)->duringBeforeAmount($node);
+        $this->shouldThrow(RuntimeException::class)->duringBeforeAmount($node);
     }
 
     function it_ignores_missing_amounts(Node $node, $output)
diff --git a/spec/Writer/TreeBuilderSpec.php b/spec/Writer/TreeBuilderSpec.php
index 86818dd..00a823e 100644
--- a/spec/Writer/TreeBuilderSpec.php
+++ b/spec/Writer/TreeBuilderSpec.php
@@ -35,7 +35,7 @@ function let(AccountNumber $bankgiro, \DateTime $date)
 
     function it_is_initializable()
     {
-        $this->shouldHaveType(TreeBuilder::CLASS);
+        $this->shouldHaveType(TreeBuilder::class);
     }
 
     function it_can_reset()
diff --git a/spec/Writer/WriterFactorySpec.php b/spec/Writer/WriterFactorySpec.php
index 1b2c2d0..7a22862 100644
--- a/spec/Writer/WriterFactorySpec.php
+++ b/spec/Writer/WriterFactorySpec.php
@@ -14,13 +14,13 @@ class WriterFactorySpec extends ObjectBehavior
 {
     function it_is_initializable()
     {
-        $this->shouldHaveType(WriterFactory::CLASS);
+        $this->shouldHaveType(WriterFactory::class);
     }
 
     function it_creates_writers(AccountNumber $bankgiro, \DateTime $date)
     {
         $bankgiro->getNumber()->willReturn('');
         $date->format(Argument::any())->willReturn('');
-        $this->createWriter('bgc_cust', $bankgiro, $date)->shouldHaveType(WriterInterface::CLASS);
+        $this->createWriter('bgc_cust', $bankgiro, $date)->shouldHaveType(WriterInterface::class);
     }
 }
diff --git a/spec/Writer/WriterSpec.php b/spec/Writer/WriterSpec.php
index c3f631a..6f710ca 100644
--- a/spec/Writer/WriterSpec.php
+++ b/spec/Writer/WriterSpec.php
@@ -25,13 +25,13 @@ function let(TreeBuilder $treeBuilder, PrintingVisitor $printer)
 
     function it_is_initializable()
     {
-        $this->shouldHaveType(Writer::CLASS);
+        $this->shouldHaveType(Writer::class);
     }
 
     function it_can_create_content($treeBuilder, $printer, Node $tree)
     {
         $treeBuilder->buildTree()->willReturn($tree)->shouldBeCalled();
-        $printer->setOutput(Argument::type(Output::CLASS))->shouldBeCalled();
+        $printer->setOutput(Argument::type(Output::class))->shouldBeCalled();
         $tree->accept($printer)->shouldBeCalled();
         $this->getContent()->shouldEqual('');
     }
diff --git a/spec/Xml/StringifierSpec.php b/spec/Xml/StringifierSpec.php
index 0b22e46..e9585a3 100644
--- a/spec/Xml/StringifierSpec.php
+++ b/spec/Xml/StringifierSpec.php
@@ -19,7 +19,7 @@ function let(MoneyFormatter $moneyFormatter)
 
     function it_is_initializable()
     {
-        $this->shouldHaveType(Stringifier::CLASS);
+        $this->shouldHaveType(Stringifier::class);
     }
 
     function it_casts_scalars()
diff --git a/spec/Xml/XmlWriterFactorySpec.php b/spec/Xml/XmlWriterFactorySpec.php
index 8363e6a..fe73c78 100644
--- a/spec/Xml/XmlWriterFactorySpec.php
+++ b/spec/Xml/XmlWriterFactorySpec.php
@@ -13,11 +13,11 @@ class XmlWriterFactorySpec extends ObjectBehavior
 {
     function it_is_initializable()
     {
-        $this->shouldHaveType(XmlWriterFactory::CLASS);
+        $this->shouldHaveType(XmlWriterFactory::class);
     }
 
     function it_can_create_writers()
     {
-        $this->createXmlWriter()->shouldHaveType(XmlWriter::CLASS);
+        $this->createXmlWriter()->shouldHaveType(XmlWriter::class);
     }
 }
diff --git a/spec/Xml/XmlWriterSpec.php b/spec/Xml/XmlWriterSpec.php
index 08e9d4d..8e8c4aa 100644
--- a/spec/Xml/XmlWriterSpec.php
+++ b/spec/Xml/XmlWriterSpec.php
@@ -20,12 +20,12 @@ function let(Stringifier $stringifier)
 
     function it_is_initializable()
     {
-        $this->shouldHaveType(XmlWriter::CLASS);
+        $this->shouldHaveType(XmlWriter::class);
     }
 
     function it_can_generate_xml(Node $node)
     {
-        $node->accept(Argument::type(XmlWritingVisitor::CLASS))->shouldBeCalled();
+        $node->accept(Argument::type(XmlWritingVisitor::class))->shouldBeCalled();
         $this->asXml($node)->shouldBeString();
     }
 }
diff --git a/spec/Xml/XmlWritingVisitorSpec.php b/spec/Xml/XmlWritingVisitorSpec.php
index bd80a86..a17f8a5 100644
--- a/spec/Xml/XmlWritingVisitorSpec.php
+++ b/spec/Xml/XmlWritingVisitorSpec.php
@@ -19,7 +19,7 @@ function let(\XMLWriter $writer, Stringifier $stringifier)
 
     function it_is_initializable()
     {
-        $this->shouldHaveType(XmlWritingVisitor::CLASS);
+        $this->shouldHaveType(XmlWritingVisitor::class);
     }
 
     function it_writes_elements_before(Node $node, $writer, $stringifier)