[RUBY] variable and method

!Mac OS X-10.15.7!ruby-2.7.1p83


Ruby variables do not require type declarations (int, char, etc. for C).

For example, assigning to a variable

name = 'Rudy'

You can do it with.


Substitute the argument ARGV [0] for the argument name

> ruby name_variable.rb Rudy
Hello Rudy.

Create a name \ _variable.rb that returns.

First, assign ARGV [0] to name \ # + begin \ _src rubyname = ARGV [0] \ # + end \ _src And \ # + begin \ _src rubyputs "Hello # {name}." \ # + end \ _src

> ruby name_variable.rb Rudy
Hello Rudy.

Is output.


In Ruby, a function defines a method.

method can take 0 or more arguments. For example

def hello(name)
  p name


> ruby hello_method.rb Rudy
Hello Rudy.

Create hello \ _method.rb that returns.

First, substitute ARGV [0] for name.

name = ARGV[0]

Then call the hello method

name = ARGV[0]

However, this gives an error because the hello method is not declared. So, create a hello method with one argument.

def hello(name)
  puts "Hello #{name}."
name = ARGV[0]

with this

> ruby hello_method.rb Rudy
Hello Rudy.

Is output.

Reference page

Chart type ruby-II (variable and method)

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