Class Sequel::SQL::Expression
In: lib/sequel/sql.rb
Parent: Object

Base class for all SQL expression objects.

Methods

==   attr_reader   comparison_attrs   eql?   hash   inspect   lit   sql_literal  

Public Class methods

attr_reader(*args)

Expression objects are assumed to be value objects, where their attribute values can‘t change after assignment. In order to make it easy to define equality and hash methods, subclass instances assume that the only values that affect the results of such methods are the values of the object‘s attributes.

[Source]

    # File lib/sequel/sql.rb, line 68
68:       def self.attr_reader(*args)
69:         super
70:         comparison_attrs.concat args
71:       end
comparison_attrs()

All attributes used for equality and hash methods.

[Source]

    # File lib/sequel/sql.rb, line 74
74:       def self.comparison_attrs
75:         @comparison_attrs ||= self == Expression ? [] : superclass.comparison_attrs.clone
76:       end

Public Instance methods

==(other)

Alias of eql?

[Source]

    # File lib/sequel/sql.rb, line 88
88:       def ==(other)
89:         eql?(other)
90:       end
eql?(other)

Returns true if the receiver is the same expression as the the other expression.

[Source]

    # File lib/sequel/sql.rb, line 94
94:       def eql?(other)
95:         other.is_a?(self.class) && !self.class.comparison_attrs.find{|a| send(a) != other.send(a)}
96:       end
hash()

Make sure that the hash value is the same if the attributes are the same.

[Source]

     # File lib/sequel/sql.rb, line 99
 99:       def hash
100:         ([self.class] + self.class.comparison_attrs.map{|x| send(x)}).hash
101:       end
inspect()

Show the class name and instance variables for the object, necessary for correct operation on ruby 1.9.2.

[Source]

     # File lib/sequel/sql.rb, line 105
105:       def inspect
106:         "#<#{self.class} #{instance_variables.map{|iv| "#{iv}=>#{instance_variable_get(iv).inspect}"}.join(', ')}>"
107:       end
lit()

Returns self, because SQL::Expression already acts like LiteralString.

[Source]

     # File lib/sequel/sql.rb, line 110
110:       def lit
111:         self
112:       end
sql_literal(ds)

Alias of to_s

[Source]

     # File lib/sequel/sql.rb, line 115
115:       def sql_literal(ds)
116:         to_s(ds)
117:       end

[Validate]