Programming Ruby: The Pragmatic Programmer's Guide

# Programming Ruby ### The Pragmatic Programmer's Guide
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class Integer |
Parent: | Numeric
Version: | 1.6

### Index:

chr downto integer? next step succ times upto

Subclasses: Bignum, Fixnum

`Integer` is the basis for the two concrete classes that hold whole numbers, `Bignum` and `Fixnum`.

instance methods
chr | int.chr -> aString
|  | Returns a string containing the ASCII character represented by the receiver's value.
`65.chr` | » | `"A"`
`?a.chr` | » | `"a"`
`230.chr` | » | `"\346"`
downto | int.downto( anInteger ) {| i | block } -> int
|  | Iterates block, passing decreasing values from int down to and including anInteger.
    5.downto(1) { |n| print n, ".. " }
    print "  Liftoff!\n"
produces:
    5.. 4.. 3.. 2.. 1..   Liftoff!
integer? | int.integer? -> `true`
|  | Always returns `true`.
next | int.next -> anInteger
|  | Returns the `Integer` equal to int + 1.
`1.next` | » | `2`
`(-1).next` | » | `0`
step | int.step( endNum, step ) {| i | block } -> int
|  | Invokes block with the sequence of numbers starting at int, incremented by step on each call. The loop finishes when the value to be passed to the block is greater than endNum (if step is positive) or less than endNum (if step is negative).
    1.step(10, 2) { |i| print i, " " }
produces:
    1 3 5 7 9
succ | int.succ -> anInteger
|  | Synonym for `Integer#next` .
times | int.times {| i | block } -> int
|  | Iterates block int times, passing in values from zero to int - 1.
    5.times do |i|
      print i, " "
    end
    print "\n"
produces:
    0 1 2 3 4
upto | int.upto( anInteger ) {| i | block } -> int
|  | Iterates block, passing in integer values from int up to and including anInteger.
    5.upto(10) { |i| print i, " " }
produces:
    5 6 7 8 9 10

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Extracted from the book "Programming Ruby - The Pragmatic Programmer's Guide"
Copyright © 2000 Addison Wesley Longman, Inc. Released under the terms of the Open Publication License V1.0.
This reference is available for download.