Class: Amalgalite::SQLite3::Database::Function

Inherits:
Object
  • Object
show all
Defined in:
lib/amalgalite/sqlite3/database/function.rb

Overview

A wrapper around a proc for use as an SQLite Ddatabase fuction

f = Function.new( 'md5', lambda { |x| Digest::MD5.hexdigest( x.to_s ) } )

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(name, _proc) ⇒ Function

Initialize with the name and the Proc



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# File 'lib/amalgalite/sqlite3/database/function.rb', line 22

def initialize( name, _proc )
  @name = name
  @function = _proc
end

Instance Attribute Details

#name ⇒ Object (readonly)

the name of the function, and how it will be called in SQL



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# File 'lib/amalgalite/sqlite3/database/function.rb', line 11

def name
  @name
end

Class Method Details

.signature(name, arity) ⇒ Object

The unique signature of this function. This is used to determin if the function is already registered or not



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# File 'lib/amalgalite/sqlite3/database/function.rb', line 16

def self.signature( name, arity )
  "#{name}/#{arity}"
end

Instance Method Details

#arity ⇒ Object

The arity of SQL function, -1 means it is takes a variable number of arguments.



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# File 'lib/amalgalite/sqlite3/database/function.rb', line 37

def arity
  @function.arity
end

#call(*args) ⇒ Object

Invoke the proc



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# File 'lib/amalgalite/sqlite3/database/function.rb', line 43

def call( *args )
  @function.call( *args )
end

#signature ⇒ Object Also known as: to_s

The unique signature of this function



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# File 'lib/amalgalite/sqlite3/database/function.rb', line 29

def signature
  @signature ||= Function.signature( name, arity )
end