Ruby variables and methods

!Mac OS X-10.15.7!ruby-2.7.1p83


Like Python, Ruby doesn't require type declaration Assign the received argument ARGV [0] to an appropriate variable and output it.

name = ARGV[0]
puts name

Execution result

$ ruby name.rb Rudy

Try to add using variables

num = ARGV[0].to_i
sum = num + num
puts sum

Execution result

$ ruby name.rb 1


A group of functions etc. will define a method This is also a bit like a Python function definition

def method name(Argument 1,Argument 2)
Process 1
Process 2

For example

def name(str1,str2)
    puts "#{str1} #{str2}"

word1 = "hello"
word2 = "world"

Execution result

$ ruby def.rb
hello world

If you want to substitute ARGV [0] and receive characters from the keyboard

def name(str1,str2)
    puts "#{str1} #{str2}."

word1 = ARGV[0]
word2 = ARGV[1]

Execution result

$ ruby def.rb hello world
hello world.

Reference article

Chart type ruby-II (variable and method)

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