The most standard error types are subclasses of StandardError
. A rescue clause without an explicit Exception
class will rescue all StandardErrors (and only those).
def foo raise "Oups" end foo rescue "Hello" #=> "Hello"
On the other hand:
require 'does/not/exist' rescue "Hi"
raises the exception:
LoadError: no such file to load -- does/not/exist
Raised when the arguments are wrong and there isn’t a more specific Exception
class.
Ex: passing the wrong number of arguments
[1, 2, 3].first(4, 5)
raises the exception:
ArgumentError: wrong number of arguments (given 2, expected 1)
Ex: passing an argument that is not acceptable:
[1, 2, 3].first(-4)
raises the exception:
ArgumentError: negative array size
Raised when a given numerical value is out of range.
[1, 2, 3].drop(1 << 100)
raises the exception:
RangeError: bignum too big to convert into `long'
The Comparable
mixin is used by classes whose objects may be ordered. The class must define the <=>
operator, which compares the receiver against another object, returning a value less than 0, returning 0, or returning a value greater than 0, depending on whether the receiver is less than, equal to, or greater than the other object. If the other object is not comparable then the <=>
operator should return nil
. Comparable
uses <=>
to implement the conventional comparison operators (<
, <=
, ==
, >=
, and >
) and the method between?
.
class SizeMatters include Comparable attr :str def <=>(other) str.size <=> other.str.size end def initialize(str) @str = str end def inspect @str end end s1 = SizeMatters.new("Z") s2 = SizeMatters.new("YY") s3 = SizeMatters.new("XXX") s4 = SizeMatters.new("WWWW") s5 = SizeMatters.new("VVVVV") s1 < s2 #=> true s4.between?(s1, s3) #=> false s4.between?(s3, s5) #=> true [ s3, s2, s5, s4, s1 ].sort #=> [Z, YY, XXX, WWWW, VVVVV]
Module Comparable provides these methods, all of which use method <=>
:
<
: Returns whether self
is less than the given object.
<=
: Returns whether self
is less than or equal to the given object.
==
: Returns whether self
is equal to the given object.
>
: Returns whether self
is greater than or equal to the given object.
>=
: Returns whether self
is greater than the given object.
between?
: Returns true
if self
is between two given objects.
clamp
: For given objects min
and max
, or range (min..max)
, returns:
min
if (self <=> min) < 0
.
max
if (self <=> max) > 0
.
self
otherwise.
Wrapper for arrays within a struct
An Array
wrapper that can be sent to another server via DRb
.
All entries in the array will be dumped or be references that point to the local server.
Cleared reference exception
This exception is raised if a parser error occurs.
This exception is raised if a generator or unparser error occurs.
Response class for Found
responses (status code 302).
The Found
response indicates that the client should look at (browse to) another URL. See 302 Found.
Response class for Temporary Redirect
responses (status code 307).
The request should be repeated with another URI
; however, future requests should still use the original URI
. See 307 Temporary Redirect.
Response class for Payload Too Large
responses (status code 413).
The request is larger than the server is willing or able to process. See 413 Payload Too Large.
Base class of exceptions from OptionParser
.