How to check if a variable is a number or a string?

Question

How to check if a variable is a number or a string in Ruby?

Answer 1

class Object
  def is_number?
    to_f.to_s == to_s || to_i.to_s == to_s
  end
end

> 15.is_number?
=> true
> 15.0.is_number?
=> true
> '15'.is_number?
=> true
> '15.0'.is_number?
=> true
> 'String'.is_number?
=> false

Answer 2

var.is_a? String

var.is_a? Numeric

Answer 3

There are several ways:

>> 1.class #=> Fixnum
>> "foo".class #=> String
>> 1.is_a? Numeric #=> true
>> "foo".is_a? String #=> true

Answer 4

if chr.to_i != 0
  puts "It is number,  yep"
end

Answer 5

Print its class, it will show you which type of variable is (e.g. String or Number).

e.g.:

puts varName.class

Answer 6

class Object
  def numeric?
    Float(self) != nil rescue false
  end
end