Predefined Variables
Ruby arguments
$!
Exception information
-c
Check
$@
Array of backtrace
-d
Debug
$&
String of last match
-e
One Line
$`
String left of last match
-h
Help
$‘
Str right of last match
-n
gets loop
Types
Expressions
Variables
$+
Last group of last match
-rL
require L
12345
if expr [then]
elsif expr
[then]
else
end
local
$N
Nth group of last match
-v
verbose
@instance
$~
Info about last match
-w
warnings
@@class
$=
Case insensitive flag
-y
comp debug
CONSTANT
$/
Input record separator
$\
Output record separator
Reserved Words
$,
Output field separator
alias
$.
Line number of last file
and
$>
Default output
BEGIN
$_
Last input line of string
begin
$*
Command line args
break
$0
Name of script
case
$$
Process number
class
$“
Module names loaded
def
$stderr
Standard error output
defined?
$stdin
Standard input
do
$stdout
Standard output
else
123.45
1.23e-4
0xFF00
1...5
unless expr
[then]
else
end
Operators and
Precedence
‚a‘..‘z‘
expr if expr
::
‚a‘...‘z‘
expr unless
expr
[]
0b01100
1..5
‚string sq‘
„string dq“
„#{expr}“
„\t\r\n“
%q(string sq)
%Q(string dq)
%(string dq)
<<id string id
:symbol
/regex/opt
%r|regex|
[1, 2, 3]
%w(1 2 3)
%W(1 2 #{expr})
{1=>2, :s=>‘v‘}
case expr
when comp
else
end
+ - ! ~
while expr [do]
end
&
until expr [do]
end
do
while expr
do
until expr
for var in expr
[do]
end
expr.each [do]
end
break next redo
retry
Exceptions
begin
rescue ex =>
var
else
ensure
end
StandardError
ZeroDivisionError
RangeError
SecurityError
IOError
IndexError
RuntimeError
**
Module/Class
module Name
end
class Name
end
class Name <
Sup
end
class << obj
end
def
name(args...)
end
def inst.
name(...)
end
public
protected
private
attr_reader
attr_writer
attr
attr_accessor
* / %
<< >>
| ^
> >= < <=
<=> == === !=
=~
elsif
&&
Regex
.. ...
.
all characters
end
= ( += -= )
[ ]
any single char in set
ensure
not
[^ ]
any single char not in set
false
and or
*
zero or more
for
+
one or more
if
?
zero or one
in
|
alteration
module
( )
Group
next
^
Beginning of line or str
nil
$
End of line or string
not
{1,5}
1 to 5
or
\A
Beginning of a string
redo
\b
Word boundary
rescue
\B
Non-word boundary
retry
\d
digit, same as [0..9]
return
\D
Non-digit
self
\s
Whitespace
super
\S
Non-whitespace
then
\w
Word-character
true
\W
Non-word-character
undef
\z
End of a string
unless
\Z
End of string, before nl
until
Constants
__FILE__
__LINE__
ENV
ARGF
ARGV
END
when
while
yield
alias new old
© 2006 mb@cenophobie.com — available free from www.cenophobie.com/ruby
Object
Array
File
Obj#class -> class
Array::new (int [,obj]) -> array
File#new (path, modestring)-> file
Obj#freeze -> object
Array#clear
Obj#frozen? -> true or false
Array#map! do |x| ... end
File#new (path, modestring) do
|file| ... end
Obj#inspect -> string
Array#delete (value) -> obj or nil
Obj#is_a? (class) -> true or false
Array#delete_at (index)-> obj or n
Obj#methods -> array
Array#delete_if do |x| ... end
Obj#respond_to? (sym) -> true or
false
Array#each do |x| ... end
File#basename (path [,suffix]) ->
string
Array#flatten! -> array
File#delete (path, ...)
Obj#to_s -> string
File#open (path, modestring) do
|file| ... end
File#exist? (path) -> t or f
Array#include? (value) -> t or f
File#rename (old, new)
Array#insert (idx, obj...)-> array
File#size (path) -> integer
String
Array#join ([string]) -> string
r
Read-only, from beginning
Str#[num, num/range/regx] -> str
Array#length -> integer
r+
Read-write, from beginning
Str#capitalize! -> string
Array#pop -> obj or nil
w
Write-only, trunc. / new
Str#center (int [,str]) -> str
Array#push (obj...) -> array
w+
Read-write, trunc. / new
Str#chomp! ([str]) -> str
Str#count -> integer
Str#delete! ([string]) -> string
Str#downcase! -> string
Str#each ([str]) do |str| ... end
Str#each_line do |line| ... end
Str#gsub! (rgx) do |match| ... end
Str#include? (str) -> true / false
Str#index (str/reg [,off]) -> int
Str#insert (int, string) -> string
Str#length -> integer
Str#ljust (int [,padstr]) -> str
a
Write-only, from end / new
Hash
a+
Read-write, from end / new
Hash#clear
b
Binary (Windows only)
Hash#delete (key) -> obj or nil
Hash#delete_if do |k, v| ... end
Dir
Hash#each do |k, v| ... end
Dir[string] -> array
Hash#has_key? (k) -> true or false
Dir::chdir ([string])
Hash#has_value? (v) -> t or f
Dir::delete (string)
Hash#index (value) -> key
Dir::entries (string) -> array
Hash#keys -> array
Dir::foreach (string) do |file|
... end
Hash#length -> integer
Str#rindex (str/reg [,off]) -> int
Hash#select do |k, v| ... end ->
array
Str#rjust (int [,padstr]) -> str
Hash#values -> array
Str#scan (rgx) do |match| ... end
Dir::getwd -> string
Dir::mkdir (string)
Dir::new (string)
Dir::open (string) do |dir| .. end
Str#split (string) -> array
Test::Unit
Dir#close
Str#strip! -> string
assert (boolean [,msg])
Dir#pos -> integer
Str#sub! (rgx) do |match| ... end
assert_block (message) do ... end
Dir#read -> string or nil
Str#swapcase! -> string
assert_equal (expected, actual
[,msg])
Dir#rewind
Str#to_sym -> symbol
Str#tr! (string, string) -> string
Str#upcase! -> string
Kernel
assert_in_delta (exp, act, dlt
[,message])
assert_kind_of (klass, object
[,msg])
block_given?
assert_match (pattern, string
[,msg])
eval (str [,binding])
assert_nil (object [,msg])
raise (exception [,string])
assert_no_match (pattern, string
[,msg])
fork do ... end => fixnum or nil
proc do ... end => proc
print (obj)
warn (msg)
assert_not_equal (expected, actual
[,msg])
DateTime
DateTime::now
DateTime::parse (str)
DateTime::strptime (str, format)
DateTime#day
DateTime#hour
DateTime#leap?
DateTime#min
DateTime#month
assert_not_nil (object [,msg])
DateTime#sec
assert_not_same (expected, actual
[,msg])
DateTime#wday
DateTime#year
assert_respond_to(obj, method
[,msg])
assert_same (expected, actual
[,msg])
Ruby: www.ruby-lang.org
Doc: www.ruby-doc.org
© 2006 mb@cenophobie.com — available free from www.cenophobie.com/ruby