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### **Summary** Closes #3212 Extends the Python `lit()` helper to natively support three additional types (`date`, `datetime`, and `Decimal`) and implements reflexive operators for the `Expr` class. This implementation specifically addresses the blocking feedback regarding precision loss, CI discovery, and query engine limitations: * **Logic Refactoring**: Simplified `lit()` by combining `date` and `datetime` normalization into ISO-8601 strings, ensuring stable SQL parsing across different engine locales. * **Precision Preservation**: `decimal.Decimal` objects are now passed as high-precision strings to the Rust bridge, bypassing intermediate float conversions and preserving full 128-bit decimal precision for DataFusion. * **Averted CI Failures**: Temporarily deferred `bytes` literal support to a future PR to resolve a known DataFusion `expr_to_sql` limitation that was crashing the `Doctest` runner. * **Reflexive Operators**: Added support for "literal-first" arithmetic and logical operations (e.g., `10 + col('a')` or `True & col('active')`). Redundant reflexive comparisons (e.g., `__rlt__`) were pruned as Python's data model handles them automatically. * **Integration Verification**: Added dedicated integration tests in the official test directory to ensure the query engine correctly handles the new types and preserves bit-perfect fidelity. ### **Changes** #### [python/python/lancedb/expr.py](file:///c:/Users/Laksh/Documents/lancedb/python/python/lancedb/expr.py) * Updated `lit()` to handle `date`, `datetime`, and `Decimal` natively. * Implemented reflexive operators (`__radd__`, `__rand__`, `__rmul__`, etc.) to support literals on the left-hand side. * Removed the problematic `bytes` doctest example and `lit()` type support to unblock CI. #### [python/src/expr.rs](file:///c:/Users/Laksh/Documents/lancedb/python/src/expr.rs) * Modified the Rust FFI bridge to extract `Decimal` objects as strings. * Ensured the `expr_lit` handler is ready to receive normalized temporal strings. * Consolidated imports and added missing operator documentation. #### [python/python/lancedb/_lancedb.pyi](file:///c:/Users/Laksh/Documents/lancedb/python/python/lancedb/_lancedb.pyi) * Updated type stubs for `expr_lit` to include `Any` (allowing for `Decimal`). ### **Testing** Added several new advanced test cases in [python/python/tests/test_expr.py](file:///c:/Users/Laksh/Documents/lancedb/python/python/tests/test_expr.py) covering: * **High-precision Decimal preservation**: Verified against 128-bit boundaries with a "one point off" test case (`1.234567890123456789 < 1.234567890123456790`). * **Reflexive operator positioning**: Verified successful query construction with literals on the left. * **Timezone-aware normalization**: Confirmed stable behavior for `datetime` objects. * **Integration Testing**: Confirmed Date32 and Decimal columns return the correct Python types and values from the engine during `.to_arrow()` calls. --------- Co-authored-by: Will Jones <willjones127@gmail.com> Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>