I understood how ruby's block works.
block_test.rb
def foo
yield if block_given?
end
my_block = foo { puts "hello" }
if I run, ruby block_test.rb. Of course it print 'hello' as you expected.
hello
But my question is when did I execute ruby block? I did not call foo method in anywhere.
I didn't write - foo() stuff like that.
# I defined `foo` method here as [If a block has been given, execute it.] but did not call.
def foo
yield if block_given?
end
# I also defined block of `foo` as [print 'hello'] and store into `my_block` variable.
# But I did not say execute `foo`. Did I?
my_block = foo { puts "hello" }
So my assumption is.. When you declare block, It implicitly means that it will execute the method with the same name of the block
Please correct me If I am missing something.
I didn't write -
foo()stuff like that.
In Ruby, parentheses are optional when calling methods. You can call a method without parentheses. For example, puts is often called without parentheses like this:
puts "hello"
You are calling your method here:
my_block = foo { puts "hello" }
# ^^^
So my assumption is.. When you declare block, It implicitly means that it will execute the method with the same name of the block
It is unclear what you are asking here. A block doesn't have a name, so "the method with the same name of the block" doesn't make sense. A block is a special argument to a method call. It cannot appear anywhere else except as the last argument of a method call. It cannot be assigned to a variable, it cannot be returned from a method, it cannot be given a name. It is not an object or a value.