Procs

Proc

p = Proc.new { puts "Hello World" }

def give_me_data(proc)
    proc.call
end

give_me_data p

# output
# Hello World

proc is like a block that can be stored in a variable

any parameter

p = Proc.new { |count| "Hello World " * count }

def give_me_data(proc)
    proc.call 5, 2
end

give_me_data p

# output
# "Hello World Hello World Hello World Hello World Hello World "

proc will attempt to return from the current context

p = Proc.new { return 10 }
p.call
# output
LocalJumpError: unexpected return

Cannot return from top-level context

def give_me_data
    puts "I'm inside the give_me_data method"
    p = Proc.new { return 10 }
    p.call # Code returns from here
    puts "I am back in give_me_data method"
end

return_value = give_me_data
puts return_value

# output
# I'm inside the give_me_data method
# 10

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