In this article, I will take you through the difference between Ruby blocks and Procs.

Ruby Blocks and Procs

Blocks

a)A Block Consists of Chunk of Code

b)Block has a name

c)Codes in the block is always enclosed within braces

d)A block is always invoked from a function with the same name as that of the block.

e)We invoke a block using yield statement.

Procs

a)PROC class can turn block into an object by wrapping blocks in its instance.

b)Proc objects are blocks of code that have been bound to a set of local variables.

c)This turns our block into a first class function and then we can perform all sorts of things with Blocks as we can do with a normal object.

Four ways to create a Proc Object

a)Using Proc.new

b)Using the Proc method in kernel module

c)Using the kernel lambda methods

d)By two implicit ways
-Using YIELD Statement

-Using Concept of &BLOCK

 

Converting between a blocks and Procs

Another common thing you will see in Ruby code is using the & operator to convert between blocks to Procs and Procs to blocks.

For example, imagine we have this method:

def do_something(&block) 
block.call 
end

When this method is called with a block, the block will be converted into a Proc. You can then use the block as if it were a Proc inside of the method:

do_something { puts "hello"}

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References: Ruby Documentation