Class: Linkage::Functions::Cast

Inherits:
Linkage::Function show all
Defined in:
lib/linkage/functions/cast.rb

Constant Summary

Constants inherited from Data

Data::TYPE_CONVERSION_TREE

Instance Attribute Summary

Attributes inherited from Linkage::Function

#args

Attributes inherited from Data

#dataset, #name

Class Method Summary collapse

Instance Method Summary collapse

Methods inherited from Linkage::Function

#==, [], #collation, #dataset, #dataset=, #initialize, #name, register, #static?

Methods inherited from Data

#collation, #database_type, #initialize, #merge, #static?

Constructor Details

This class inherits a constructor from Linkage::Function

Class Method Details

.function_name ⇒ Object 



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# File 'lib/linkage/functions/cast.rb', line 4

def self.function_name
  "cast"
end

.parameters ⇒ Object 



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# File 'lib/linkage/functions/cast.rb', line 8

def self.parameters
  [[:any], [String]]
end

Instance Method Details

#ruby_type ⇒ Object 



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# File 'lib/linkage/functions/cast.rb', line 12

def ruby_type
  type =
    case @values[1]
    when 'integer'
      Fixnum
    when 'binary'
      File
    else
      raise "unknown type: #{@values[1]}"
    end

  {:type => type}
end

#to_expr(options = {}) ⇒ Object 



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# File 'lib/linkage/functions/cast.rb', line 26

def to_expr(options = {})
  cast =
    case @values[1]
    when 'integer'
      case dataset.database_type
      when :sqlite, :postgres, :h2
        :integer
      when :mysql
        :signed
      end
    when 'binary'
      case dataset.database_type
      when :sqlite
        :blob
      when :postgres
        :bytea
      when :mysql, :h2
        :binary
      end
    end

  if cast
    @values[0].cast(cast)
  end
end