Array.insert / delete / delete_at / compact

# Inserts one or more elements at the specified index.
array.insert(index, element, ...)

# Removes all elements matching the specified value.
array.delete(value)
array.delete(value) { return_value_if_not_found }

# Removes the element at the specified index.
array.delete_at(index)

# Returns a new array with nil elements removed.
array.compact

# Removes nil elements in place (destructive).
array.compact!

colors = ["red", "blue", "yellow"]

# Insert "green" at index 1 using insert.
colors.insert(1, "green")
puts colors.inspect  # ["red", "green", "blue", "yellow"]

# Multiple elements can be inserted at once.
colors.insert(2, "purple", "orange")
puts colors.inspect  # ["red", "green", "purple", "orange", "blue", "yellow"]

# Remove a value using delete.
colors.delete("orange")
puts colors.inspect  # ["red", "green", "purple", "blue", "yellow"]

# Use a block to specify a default return value when the element is not found.
result = colors.delete("white") { "not found" }
puts result  # not found

# Remove by index using delete_at.
removed = colors.delete_at(0)
puts removed        # red
puts colors.inspect  # ["green", "purple", "blue", "yellow"]

# Remove nil values using compact.
data = [1, nil, 2, nil, 3, nil]
puts data.compact.inspect  # [1, 2, 3]
puts data.inspect           # [1, nil, 2, nil, 3, nil] (original unchanged)

# Modify the array in place using compact!.
data.compact!
puts data.inspect  # [1, 2, 3]

Use insert to add elements in the middle of an array. For appending to the end, push or << is faster. Use delete to remove elements by value, and delete_at to remove an element by index.

delete removes all elements that match the given value, so if the same value appears multiple times, every occurrence will be deleted. Use delete_at when you need to remove only the element at a specific position.

Use compact to clean up unwanted nil values that appear as a result of array processing. To remove duplicate elements, use uniq. For operations at the end or beginning of an array, use push / pop / shift / unshift.