ruby_methods.rb

# .upto

95.upto(100) { |num| print num, " " }
# Prints 95 96 97 98 99 100

# works for letters too!
"L".upto("P") { |letter| puts letter }

# .downto
# opposite of .upto


# .respond_to(:method)

#Ruby is less concerned about what kind of thing an object is and only really cares about what method calls it responds to.

#Remember when we mentioned that symbols are awesome for referencing method names? Well, .respond_to? takes a symbol and returns true if an object can receive that method and false otherwise. For example,

#[1, 2, 3].respond_to?(:push)

#would return true, since you can call .push on an array object. However,

#[1, 2, 3].respond_to?(:to_sym)

#would return false, since you can't turn an array into a symbol.

#Rather than checking to see if our age variable is an integer, check to see if it will .respond_to? the .next method. (.next will return the integer immediately following the integer it's called on, meaning 4.next will return 5.)

age = 26
age.respond_to?(:next)