Conditional Statements in Elixir

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Conditional Statements in Elixir[edit]

Elixir is a functional programming language that provides several conditional statements to control the flow of execution in the program. These statements allow developers to make decisions based on certain conditions and execute specific sets of code accordingly.

If Statements[edit]

The `if` statement in Elixir is used to evaluate a condition and execute a block of code if the condition is true. It has the following syntax:

```elixir if condition do

 # Code to execute if condition is true

else

 # Code to execute if condition is false

end ```

Unless Statements[edit]

The `unless` statement in Elixir is the opposite of the `if` statement. It executes a block of code only if the condition is false. The syntax is as follows:

```elixir unless condition do

 # Code to execute if condition is false

else

 # Code to execute if condition is true

end ```

Case Statements[edit]

The `case` statement in Elixir is used for pattern matching and branching based on different conditions. It allows developers to handle multiple cases with different code blocks. The syntax for a `case` statement is as follows:

```elixir case expression do

 pattern1 ->
   # Code to execute if expression matches pattern1
 
 pattern2 ->
   # Code to execute if expression matches pattern2
 
 ...
 
 _ ->
   # Code to execute if expression matches none of the patterns

end ```

Cond Statements[edit]

The `cond` statement in Elixir is used to evaluate multiple conditions sequentially and execute the code block associated with the first true condition. It is useful when there are multiple conditions to consider. The syntax for a `cond` statement is as follows:

```elixir cond do

 condition1 ->
   # Code to execute if condition1 is true
 
 condition2 ->
   # Code to execute if condition2 is true
 
 ...
 
 true ->
   # Code to execute if none of the conditions are true

end ```

Guard Clauses[edit]

In Elixir, guard clauses are used to add additional conditions to function clauses. They allow developers to specify conditions that must be met in order for a function to be executed. Guard clauses use the `when` keyword followed by the condition. Here's an example:

```elixir def fun(arg) when condition do

 # Code to execute if condition is true

end ```

Guard clauses can also be used inside `case` and `cond` statements to specify conditions for individual patterns or conditions.

Conclusion[edit]

Conditional statements play a crucial role in controlling the flow of execution in Elixir programs. With `if`, `unless`, `case`, and `cond` statements, developers can write expressive and efficient code that handles different scenarios based on conditions. Guard clauses provide an additional level of control within function definitions. Mastering these conditional statements is essential for writing robust Elixir applications.

See also: