[span] remove the _elementsEqual() functions

We should only add them once they reach their final form.

Author: glessard

stdlib/public/core/Span/Span.swift

@@ -323,89 +323,6 @@ extension Span where Element: BitwiseCopyable {
   }
 }
 
-@_disallowFeatureSuppression(NonescapableTypes)
-@available(SwiftStdlib 6.1, *)
-extension Span where Element: Equatable {
-
-  /// Returns a Boolean value indicating whether this and another span
-  /// contain equal elements in the same order.
-  ///
-  /// - Parameters:
-  ///   - other: A span to compare to this one.
-  /// - Returns: `true` if this sequence and `other` contain equivalent items,
-  ///   using `areEquivalent` as the equivalence test; otherwise, `false.`
-  ///
-  /// - Complexity: O(*m*), where *m* is the lesser of the length of the
-  ///   sequence and the length of `other`.
-  @_disallowFeatureSuppression(NonescapableTypes)
-  @_alwaysEmitIntoClient
-  public func _elementsEqual(_ other: Self) -> Bool {
-    guard count == other.count else { return false }
-    if count == 0 { return true }
-
-    // This could be short-cut with a layout constraint
-    // where stride equals size, as long as there is
-    // at most 1 unused bit pattern, e.g.:
-    // if Element is BitwiseEquatable {
-    // return _swift_stdlib_memcmp(lhs.baseAddress, rhs.baseAddress, count) == 0
-    // }
-    if _pointer != other._pointer {
-      for o in 0..<count {
-        if self[unchecked: o] != other[unchecked: o] { return false }
-      }
-    }
-    return true
-  }
-
-  /// Returns a Boolean value indicating whether this span and a Collection
-  /// contain equal elements in the same order.
-  ///
-  /// - Parameters:
-  ///   - other: A Collection to compare to this span.
-  /// - Returns: `true` if this sequence and `other` contain equivalent items,
-  ///   using `areEquivalent` as the equivalence test; otherwise, `false.`
-  ///
-  /// - Complexity: O(*m*), where *m* is the lesser of the length of the
-  ///   sequence and the length of `other`.
-  @_disallowFeatureSuppression(NonescapableTypes)
-  @_alwaysEmitIntoClient
-  public func _elementsEqual(_ other: some Collection<Element>) -> Bool {
-#if hasFeature(LifetimeDependence)
-    let equal = other.withContiguousStorageIfAvailable {
-      _elementsEqual(Span(_unsafeElements: $0))
-    }
-    if let equal { return equal }
-#endif
-
-    guard count == other.count else { return false }
-    if count == 0 { return true }
-
-    return _elementsEqual(AnySequence(other))
-  }
-
-  /// Returns a Boolean value indicating whether this span and a Sequence
-  /// contain equal elements in the same order.
-  ///
-  /// - Parameters:
-  ///   - other: A Sequence to compare to this span.
-  /// - Returns: `true` if this sequence and `other` contain equivalent items,
-  ///   using `areEquivalent` as the equivalence test; otherwise, `false.`
-  ///
-  /// - Complexity: O(*m*), where *m* is the lesser of the length of the
-  ///   sequence and the length of `other`.
-  @_disallowFeatureSuppression(NonescapableTypes)
-  @_alwaysEmitIntoClient
-  public func _elementsEqual(_ other: some Sequence<Element>) -> Bool {
-    var offset = 0
-    for otherElement in other {
-      if offset >= count { return false }
-      if self[unchecked: offset] != otherElement { return false }
-      offset += 1
-    }
-    return offset == count
-  }
-}
-
 @_disallowFeatureSuppression(NonescapableTypes)
 @available(SwiftStdlib 6.1, *)
 extension Span where Element: ~Copyable {