Module: SciYAG::Backends::Descriptions::Conversion

Included in:
Parameter
Defined in:
lib/SciYAG/Backends/descriptions.rb

Overview

A module to convert text input into an object of the given type.

Constant Summary collapse

TRUE_RE =

The regular expression that matches ‘true’ for boolean values:

/^\s*(true|yes)\s*$/i
FALSE_RE =

The regular expression that matches ‘false’

/^\s*(false|no(ne)?)\s*$/i

Instance Method Summary collapse

Instance Method Details

#text_to_type(text, type) ⇒ Object

Converts text to the given type. It support different schemes:

  • if type is String, Float, Array of Integer, the values are converted using the appropriate functions;

  • if type is a string, the type is considered to be String; this leaves a possibility to implement a more precise mechanism for choosing; see Descriptions::Parameter#type

  • if type is :bool, the text is interpreted as a true/false expression.

  • if type is an array (of symbols/strings), then a valid input is one of the elements of the arrays (it is converted to symbols if necessary)

  • if type is a hash, it behaves as if the keys had been specified as an array. The values can be used to provide a proper name;

  • for any other input, type is assumed to be a class, and its constructor should support build from 1 argument, a String.



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# File 'lib/SciYAG/Backends/descriptions.rb', line 51

def text_to_type(text, type)
  # warning: case cannot be used, as it is the comparison
  # === which is used, that is is_a?.
  if type == String
    value = String(text)
  elsif type.is_a?(String) # some special specification;
    # always a string
    value = String(text)
  elsif type == Float
    value = Float(text)
  elsif type == Array
    value = Array(text)
  elsif type == Integer 
    value = Integer(text)
  elsif type.is_a?(Array)
    h = {}
    type.each do |a|
      h[a.to_s] = a
    end
    return h[text]        # No checking done...
  elsif type.is_a?(Hash)
    return text_to_type(text, type.keys)
  elsif type == :bool
    if text =~ TRUE_RE
      return true
    else
      return false
    end
  else
    value = type.new(text)
  end
  return value
end