Class: Arrow::Expression

Inherits:
Object
  • Object
show all
Defined in:
lib/arrow/expression.rb

Class Method Summary collapse

Class Method Details

.try_convert(value) ⇒ Object

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future. 



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# File 'lib/arrow/expression.rb', line 22

def try_convert(value)
  case value
  when Symbol
    FieldExpression.new(value.to_s)
  when ::Array
    function_name, *arguments = value
    case function_name
    when String, Symbol
      function_name = function_name.to_s
    else
      return nil
    end
    options = nil
    if arguments.last.is_a?(FunctionOptions)
      options = arguments.pop
    elsif arguments.last.is_a?(Hash)
      function = Function.find(function_name)
      if function
        options = function.resolve_options(arguments.pop)
      end
    end
    CallExpression.new(function_name, arguments, options)
  else
    datum = Datum.try_convert(value)
    return nil if datum.nil?
    LiteralExpression.new(datum)
  end
end