1 files changed, 29 insertions, 0 deletions
diff --git a/lib/gitlab/ci/pipeline/expression/lexeme/base.rb b/lib/gitlab/ci/pipeline/expression/lexeme/base.rb
new file mode 100644
index 00000000000..29b73c94358
--- /dev/null
+++ b/lib/gitlab/ci/pipeline/expression/lexeme/base.rb
@@ -0,0 +1,29 @@
+module Gitlab
+  module Ci
+    module Pipeline
+      module Expression
+        module Lexeme
+          class Base
+            def evaluate(**variables)
+              raise NotImplementedError
+            end
+
+            def self.build(token)
+              raise NotImplementedError
+            end
+
+            def self.type
+              self::TYPE
+            end
+
+            def self.scan(scanner)
+              if scanner.scan(self::PATTERN)
+                Expression::Token.new(scanner.matched, self)
+              end
+            end
+          end
+        end
+      end
+    end
+  end
+end