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Ruby Ruby Foundations Procs & Lambdas Working With Procs & Lambdas

Víctor Rico
Víctor Rico
17,808 Points
Posted by Víctor Rico
Víctor Rico
17,808 Points

Is this really a good example about why procs and lambdas are useful?

I changed the Paper class a bit to see if I could make it work with less code. This is what I did and it worked:

class Paper 
    def initialize(&block) 
        yield self if block_given?
    end

    def set_variable(kind, val)
        return [kind, val].join ": "
    end

    def title(value)
        @title = set_variable "TITLE", value
    end

    def heading(value)
        @heading = set_variable "HEADING", value
    end

    def body(value)
        @body = set_variable "BODY", value
    end

    def display
        puts @title
        puts "______________________"
        puts @heading
        puts "______________________"
        puts @body
        puts "______________________"
    end
end

paper = Paper.new do |p| 
    p.title     "My awesome paper"
    p.heading "This is my paper"
    p.body      "The entire contents of my paper would go here."
end
paper.display

Could anyone explain a better scenario for woking with procs or lambdas?

Thank you very much!

Víctor Rico
Víctor Rico
17,808 Points
Víctor Rico
Víctor Rico
17,808 Points

I think blocks are like Javascript anonymous functions:

some_method(function() {
  //Code here...
});

And procs and lambdas would be something like this:

var example = function(arg1, arg2) {
  //Code here...
};

Am I right?