Comparing python objects (such as list/tuple) with mlx.core.array (#920)

* add implicit conversion of list to array for equality constraint

* add tests for array equality

* add test for tuple and array equality

* return False if __eq__ arg is list or tuple

* write tests for equality

* update the rule of comparison for __ge__/__gt__/__lt__/__le__

* add a helper function for detecting mlx.core.array

* return true in case fo inequality

* debug minor issue regarding detecting mlx array

* add tests for inequality comparisons

* add name for contribution

* reformat files using pre-commit

* update tests for float

* update tests for inequality

* raise exception in case of invalid comparisons

* use isinstance instead of string comparison

* replace "is_convirtable_to_array" with previous logic

* remove throwing exceptions for other operations

* just a comment

* minor changes for efficiency

* optimize a utils function

* change the function name

* Update ACKNOWLEDGMENTS.md

---------

Co-authored-by: Awni Hannun <awni.hannun@gmail.com>

python/src/utils.h

@@ -44,6 +44,18 @@ inline array to_array_with_accessor(nb::object obj) {
   }
 }
 
+inline bool is_comparable_with_array(const ScalarOrArray& v) {
+  // Checks if the value can be compared to an array (or is already an
+  // mlx array)
+  if (auto pv = std::get_if<nb::object>(&v); pv) {
+    return nb::isinstance<array>(*pv) || nb::hasattr(*pv, "__mlx_array__");
+  } else {
+    // If it's not an object, it's a scalar (nb::int_, nb::float_, etc.)
+    // and can be compared to an array
+    return true;
+  }
+}
+
 inline array to_array(
     const ScalarOrArray& v,
     std::optional<Dtype> dtype = std::nullopt) {