To split a list by a keyword in Elixir, you can use the Enum.chunk_by/4 function. This function takes in a list, a keyword, a boolean function, and a keyword list as arguments. The list will be split into sublists based on the given keyword and boolean function. The keyword list is used to specify additional options for splitting the list.
For example, if you have a list of strings and you want to split it into sublists based on the keyword "hello", you can use the following code:
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list = ["hello", "world", "hello", "elixir"] keyword = "hello" result = Enum.chunk_by(list, &(&1 == keyword), keyword: true) IO.inspect(result) |
This code will split the list ["hello", "world", "hello", "elixir"] into two sublists: ["hello", "world"] and ["hello", "elixir"], based on the keyword "hello". You can then further process or manipulate these sublists as needed.
What is a keyword in Elixir?
A keyword in Elixir is a special kind of data structure that consists of a list of key-value pairs, where keys are atoms and values can be any Elixir data type. Keywords are commonly used to pass options or named arguments to functions in Elixir, and they are typically written using square brackets with a colon separating the key and value (e.g., [name: "Alice", age: 30]). Keywords are also useful for pattern matching and destructuring in Elixir code.
What is the difference between a tuple and a keyword list in Elixir?
In Elixir, a tuple is an ordered collection of elements where each element can be of any type. Tuples are defined using curly braces {} and elements are separated by commas. For example, {1, "hello", :world} is a tuple with three elements.
On the other hand, a keyword list is a special type of list where each element is a key-value pair. Keys are atoms (symbols that start with a colon) and values can be of any type. Keyword lists are defined using square brackets [] with key-value pairs separated by commas. For example, [{:name, "John"}, {:age, 30}] is a keyword list with two key-value pairs.
The main difference between tuples and keyword lists in Elixir is their structure and how they are used. Tuples are typically used to group related data together in a fixed order, while keyword lists are commonly used to pass named arguments or options to functions. Another key difference is that tuples maintain the order of elements, while keyword lists do not guarantee the order of key-value pairs.
What is pattern matching in Elixir?
Pattern matching in Elixir is a powerful feature that allows you to destructure data and bind variables based on a given pattern. It is a fundamental concept in Elixir and is used in functions, case statements, and when clauses.
In Elixir, you can use pattern matching to match against different data types such as lists, tuples, maps, and structs. By using pattern matching, you can write concise and readable code that handles different cases or conditions without using complex if-else statements.
Pattern matching also allows you to nest patterns and extract values from complex data structures easily. It is a key feature in functional programming languages like Elixir that enables you to write code that is clear, concise, and expressive.
