(WIP) feat: Predicate basic implementation

src/iceberg/CMakeLists.txt

@@ -23,6 +23,7 @@ set(ICEBERG_SOURCES
     demo.cc
     expression/expression.cc
     expression/literal.cc
+    expression/term.cc
     file_reader.cc
     json_internal.cc
     manifest_entry.cc

src/iceberg/expression/common.h

@@ -0,0 +1,141 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+#pragma once
+
+#include <memory>
+#include <string>
+
+#include "iceberg/result.h"
+#include "iceberg/schema.h"
+
+namespace iceberg {
+
+/// Operation types for expressions
+enum class Operation {
+  kTrue,
+  kFalse,
+  kIsNull,
+  kNotNull,
+  kIsNan,
+  kNotNan,
+  kLt,
+  kLtEq,
+  kGt,
+  kGtEq,
+  kEq,
+  kNotEq,
+  kIn,
+  kNotIn,
+  kNot,
+  kAnd,
+  kOr,
+  kStartsWith,
+  kNotStartsWith,
+  kCount,
+  kCountStar,
+  kMax,
+  kMin
+};
+
+/// \brief Returns whether the operation is a predicate operation.
+constexpr bool IsPredicate(Operation op) {
+  switch (op) {
+    case Operation::kTrue:
+    case Operation::kFalse:
+    case Operation::kIsNull:
+    case Operation::kNotNull:
+    case Operation::kIsNan:
+    case Operation::kNotNan:
+    case Operation::kLt:
+    case Operation::kLtEq:
+    case Operation::kGt:
+    case Operation::kGtEq:
+    case Operation::kEq:
+    case Operation::kNotEq:
+    case Operation::kIn:
+    case Operation::kNotIn:
+    case Operation::kNot:
+    case Operation::kAnd:
+    case Operation::kOr:
+    case Operation::kStartsWith:
+    case Operation::kNotStartsWith:
+      return true;
+    case Operation::kCount:
+    case Operation::kCountStar:
+    case Operation::kMax:
+    case Operation::kMin:
+      return false;
+  }
+  return false;
+}
+
+constexpr bool IsUnaryPredicate(Operation op) {
+  switch (op) {
+    case Operation::kIsNull:
+    case Operation::kNotNull:
+    case Operation::kIsNan:
+    case Operation::kNotNan:
+      return true;
+    default:
+      return false;
+  }
+}
+constexpr bool IsBinaryPredicate(Operation op) {
+  switch (op) {
+    case Operation::kLt:
+    case Operation::kLtEq:
+    case Operation::kGt:
+    case Operation::kGtEq:
+    case Operation::kEq:
+    case Operation::kNotEq:
+    case Operation::kIn:
+    case Operation::kNotIn:
+    case Operation::kAnd:
+    case Operation::kOr:
+    case Operation::kStartsWith:
+    case Operation::kNotStartsWith:
+      return true;
+    default:
+      return false;
+  }
+}
+
+template <typename T>
+concept Bindable = requires(const T& expr, const Schema& schema, bool case_sensitive) {
+  // Must have a BoundType alias that defines what type it binds to
+  typename T::BoundType;
+  // Must have a Bind method with the correct signature
+  { expr.Bind(schema, case_sensitive) } -> std::same_as<Result<typename T::BoundType>>;
+};
+
+/// \brief Concept for types that behave like predicates (bound or unbound)
+template <typename T>
+concept PredicateLike = requires(const T& pred) {
+  // Must have an operation type
+  { pred.op() } -> std::same_as<Operation>;
+  // Must be convertible to string
+  { pred.ToString() } -> std::same_as<std::string>;
+  // // Must have a Negate method that returns a shared_ptr to the same concept
+  // { pred.Negate() } -> std::convertible_to<std::shared_ptr<T>>;
+  // Must support equality comparison
+  { pred.Equals(pred) } -> std::same_as<bool>;
+};
+
+}  // namespace iceberg