Revert "enforce [[nodiscard]]"

This reverts commit 2708d07.

Author: zhjwpku

.clang-tidy

@@ -21,6 +21,7 @@ Checks: |
   clang-analyzer-*,
   google-*,
   modernize-*,
+  -modernize-use-nodiscard,
   -modernize-use-trailing-return-type,
 
 CheckOptions:

src/iceberg/arrow/demo_arrow.h

@@ -30,7 +30,7 @@ class ICEBERG_ARROW_EXPORT DemoArrow : public Table {
  public:
   DemoArrow() = default;
   ~DemoArrow() override = default;
-  [[nodiscard]] std::string print() const override;
+  std::string print() const override;
 };
 
 }  // namespace iceberg::arrow

src/iceberg/demo_table.h

@@ -28,7 +28,7 @@ class ICEBERG_EXPORT DemoTable : public Table {
   DemoTable() = default;
   ~DemoTable() override = default;
 
-  [[nodiscard]] std::string print() const override;
+  std::string print() const override;
 };
 
 }  // namespace iceberg

src/iceberg/puffin.h

@@ -28,7 +28,7 @@ namespace iceberg {
 class ICEBERG_EXPORT Puffin {
  public:
   virtual ~Puffin() = default;
-  [[nodiscard]] virtual std::string print() const = 0;
+  virtual std::string print() const = 0;
 };
 
 }  // namespace iceberg

src/iceberg/puffin/demo_puffin.h

@@ -28,7 +28,7 @@ class ICEBERG_PUFFIN_EXPORT DemoPuffin : public Puffin {
  public:
   DemoPuffin() = default;
   ~DemoPuffin() override = default;
-  [[nodiscard]] std::string print() const override;
+  std::string print() const override;
 };
 
 }  // namespace iceberg::puffin

src/iceberg/table.h

@@ -29,7 +29,7 @@ namespace iceberg {
 class ICEBERG_EXPORT Table {
  public:
   virtual ~Table() = default;
-  [[nodiscard]] virtual std::string print() const = 0;
+  virtual std::string print() const = 0;
 };
 
 }  // namespace iceberg