Ruby Programming/Reference/Objects/Numeric/Integer

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Integer provides common behavior of integers (Fixnum and Bignum). Integer is an abstract class, so you should not instantiate this class.

Inherited Class: Numeric Included Module: Precision

Class Methods:

Integer::induced_from(numeric)

   Returns the result of converting numeric into an integer.

Instance Methods:

Bitwise operations: AND, OR, XOR, and inversion.

~i
i & int
i | int
i ^ int
i << int
i >> int

   Bitwise left shift and right shift.

i[n]

   Returns the value of the nth bit from the least significant bit, which is i[0].
   5[0]      # => 1
   5[1]      # => 0
   5[2]      # => 1

i.chr

   Returns a string containing the character for the character code i.
   65.chr    # => "A"
   ?a.chr    # => "a"

i.downto( min) {| i| ...}

   Invokes the block, decrementing each time from i to min.
   3.downto(1) {|i|
     puts i
   }
   # prints:
   #  3
   #  2
   #  1  

i.next
i.succ

   Returns the next integer following i. Equivalent to i + 1.

i.size

   Returns the number of bytes in the machine representation of i.

i.step( upto, step) {| i| ...}

   Iterates the block from i to upto, incrementing by step each time.
   10.step(5, -2) {|i|
     puts i
   }
   # prints:
   #  10
   #  8
   #  6  

i.succ

   See i.next

i.times {| i| ...}

   Iterates the block i times.
   3.times {|i|
     puts i
   }
   # prints:
   #  0
   #  1
   #  2

i.to_f

   Converts i into a floating point number. Float conversion may lose precision information.
   1234567891234567.to_f   # => 1.234567891e+15

i.to_int

   Returns i itself. Every object that has to_int method is treated as if it's an integer.

i.upto( max) {| i| ...}

   Invokes the block, incrementing each time from i to max.
   1.upto(3) {|i|
     puts i
   }
   # prints:
   #  1  
   #  2
   #  3