Functional Programming in Ruby 1.9

Blocks are just a special syntactic sugar in Ruby to create Procs.
Lambdas are really just Procs, but with two important differences:
Lambdas check the arguments they receive, just like methods. Procs do not. This means if you pass only one argument to a Lambda that takes two arguments, you’ll get an ArgumentError. If you do the same to a Proc, it will just blindly accept the ones you did give, and set the rest of the arguments to nil;
Any return statements used in a Proc will also return from the method that called that Proc. Lambdas, on the other hand, will not. This means you can call a Lambda, get its return value, and process it, all within the one method;
Currying is the ability to take a function that accepts n parameters and generate from it one of more functions with some parameter values already filled in. In RUby 1.9, you create a curry-able proc by calling the curry method on it. If you subsequently call this curried proc with fewer parameters than it expects, it will not execute. Instead, it returns a new proc with those parameters already bound;

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