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.
WIN32OLE_PARAM
objects represent param information of the OLE method.
Cleared reference exception
This exception is raised if a parser error occurs.
This exception is raised if a generator or unparser error occurs.
Base class of exceptions from OptionParser
.