def all?(&block)
each { |item| return false unless block.call(item) }
true
end
This is a Ruby method definition for `all?`. Here’s what each line does:
1. `def all?(&block)`: This line defines a method named `all?` that takes a block as an argument. The `&block` syntax allows you to pass a block to the method and treat it as a `Proc` object. In this case, `&block` signifies that the method is expecting a block to be passed in when it is called.
2. `each { |item| return false unless block.call(item) }`: This line uses the `each` method to iterate over a collection (presumably, the collection that this method is being called on). For each element in the collection, it executes the code within the block.
– `|item|` is a block parameter that represents each individual element in the collection.
– `block.call(item)` calls the block that was passed into the `all?` method (referenced as `&block`), passing in the current element (`item`). The result of this call is evaluated as a boolean condition.
If the block call returns `false` for any element, the `return false` statement exits the method immediately, indicating that not all elements satisfy the condition.
3. `true`: If the method has iterated through all elements in the collection without returning `false`, it means that the condition specified in the block was met for every element. In this case, the method returns `true`, indicating that all elements passed the condition.
To give you an example of how this method might be used:
“`ruby
numbers = [2, 4, 6, 8]
result = numbers.all? { |num| num.even? }
puts result # This will output: true
“`
In this example, `all?` is called on the `numbers` array with a block that checks if each number is even. Since all the numbers in the array are even, the method returns `true`. If any number were odd, `all?` would return `false`.