How to Split A List By Keyword In Elixir?

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To split a list by a keyword in Elixir, you can use the Enum.split_with/2 function. This function takes two arguments: the list you want to split and a function that determines whether an element should be split. The function should return a tuple where the first element is a boolean indicating if the element should be split and the second element is the value to split by.


For example, if you have a list of strings and you want to split it by the keyword "apple", you can use the following code:

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list = ["banana", "orange", "apple", "apple", "grape"]
{before, after} = Enum.split_with(list, fn x -> x != "apple" end)


In this code, before will contain ["banana", "orange"] and after will contain ["apple", "apple", "grape"]. This is because the Enum.split_with function splits the list on the first occurrence of the keyword "apple" and includes the keyword in the second part of the split.

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How to handle splitting a large list by keyword in Elixir?

One way to handle splitting a large list by keyword in Elixir is to use the Enum.chunk_by/2 function along with a custom predicate function that checks if the keyword is found in each item.


Here's an example implementation:

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list = ["apple", "banana", "cherry", "apple", "date", "banana", "fig", "grape"]

keyword = "banana"

is_keyword = fn item -> item == keyword end

split_list = Enum.chunk_by(list, is_keyword)

IO.inspect(split_list)


This code will split the list into sublists based on the keyword "banana". The resulting output will be a list of sublists where each sublist contains consecutive elements until the keyword is found.


You can modify the is_keyword predicate function to match your specific criteria for identifying the keyword in the list.


How to handle duplicates in the input list when splitting by keyword in Elixir?

One way to handle duplicates in the input list when splitting by a keyword in Elixir is to use the Enum.uniq/1 function to remove duplicates before splitting the list. Here is an example code snippet to demonstrate this:

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input_list = ["keyword", "item1", "keyword", "item2", "keyword", "item3", "keyword", "item1", "keyword", "item4"]
keyword = "keyword"

# Remove duplicates from the input list
input_list = Enum.uniq(input_list)

# Split the input list by the keyword
split_list = Enum.split(input_list, &(&1 == keyword))

IO.inspect(split_list)


In this code snippet, we first remove duplicates from the input_list using Enum.uniq/1. Then, we split the list by the keyword using the Enum.split/2 function. This will give us a list where each sublist starts with the keyword and contains the corresponding items following the keyword without any duplicates.


How to split a list using a specific keyword in Elixir?

You can split a list using a specific keyword in Elixir by using the Enum.split_while/2 function. This function splits a list into two sublists, based on a given condition.


Here's an example of how you can split a list using a specific keyword:

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list = ["apple", "banana", "kiwi", "orange", "pear"]

{before_keyword, after_keyword} = Enum.split_while(list, &(&1 != "orange"))

IO.inspect(before_keyword) # Output: ["apple", "banana", "kiwi"]
IO.inspect(after_keyword)  # Output: ["orange", "pear"]


In this example, the Enum.split_while/2 function splits the list into two sublists before_keyword and after_keyword, based on the condition that the keyword is "orange". The before_keyword list contains elements before the keyword while the after_keyword list contains elements after the keyword.


You can replace "orange" with any other keyword that you want to use for splitting the list.

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