note: per issue #656 , this is the second attempt after cleaning up the code.

This PR adds a new Clone function to the slice utilities that returns a shallow copy of any slice collection.

Implementation

The Clone function uses the efficient append(collection[:0:0], collection...) pattern to create a shallow copy:

// Clone returns a shallow copy of the collection.
func Clone[T any](collection []T) []T {
	return append(collection[:0:0], collection...)
}

Usage

original := []int{1, 2, 3, 4, 5}
cloned := lo.Clone(original)

// Modifying the clone doesn't affect the original
cloned[0] = 99
fmt.Println(original) // [1 2 3 4 5]
fmt.Println(cloned)   // [99 2 3 4 5]

Features

• Type-safe: Works with any slice type using Go generics
• Efficient: Uses the slice reslicing pattern for optimal performance
• Nil-safe: Properly handles nil slices by returning nil
• Independence: Creates truly independent copies that don't share underlying arrays

Testing

Added comprehensive tests covering:

• Various slice types (int, string)
• Empty slices
• Nil slices
• Verification that modifications to cloned slices don't affect originals
• Example tests demonstrating usage

All existing tests continue to pass, ensuring no regressions.

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