Class: Hash

Inherits:
Object show all
Defined in:
lib/merb-core/core_ext/hash.rb

Direct Known Subclasses

Mash, Merb::SimpleSet

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

.from_xml(xml) ⇒ Object

Converts valid XML into a Ruby Hash structure.

Paramters

xml<String>

A string representation of valid XML.

Notes

  • Mixed content is treated as text and any tags in it are left unparsed

  • Any attributes other than type on a node containing a text node will be discarded

Typecasting

Typecasting is performed on elements that have a type attribute:

integer
boolean

Anything other than “true” evaluates to false.

datetime

Returns a Time object. See Time documentation for valid Time strings.

date

Returns a Date object. See Date documentation for valid Date strings.

Keys are automatically converted to snake_case

Examples

Standard
<user gender='m'>
  <age type='integer'>35</age>
  <name>Home Simpson</name>
  <dob type='date'>1988-01-01</dob>
  <joined-at type='datetime'>2000-04-28 23:01</joined-at>
  <is-cool type='boolean'>true</is-cool>
</user>

evaluates to 

{ "user" => { 
    "gender"    => "m",
    "age"       => 35,
    "name"      => "Home Simpson",
    "dob"       => DateObject( 1998-01-01 ),
    "joined_at" => TimeObject( 2000-04-28 23:01),
    "is_cool"   => true 
  }
}
Mixed Content
<story>
  A Quick <em>brown</em> Fox
</story>

evaluates to

{ "story" => "A Quick <em>brown</em> Fox" }
Attributes other than type on a node containing text
<story is-good='false'>
  A Quick <em>brown</em> Fox
</story>

evaluates to

{ "story" => "A Quick <em>brown</em> Fox" }

<bicep unit='inches' type='integer'>60</bicep>

evaluates with a typecast to an integer. But unit attribute is ignored.

{ "bicep" => 60 }



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# File 'lib/merb-core/core_ext/hash.rb', line 72

def from_xml( xml )
  ToHashParser.from_xml(xml)
end

Instance Method Details

#add_html_class!(html_class) ⇒ Object

Parameters

html_class<~to_s>

The HTML class to add to the :class key. The html_class will be concatenated to any existing classes.

Examples

hash[:class] #=> nil
hash.add_html_class!(:selected)
hash[:class] #=> "selected"
hash.add_html_class!("class1 class2")
hash[:class] #=> "selected class1 class2"



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# File 'lib/merb-core/core_ext/hash.rb', line 174

def add_html_class!(html_class)
  if self[:class]
    self[:class] = "#{self[:class]} #{html_class}"
  else
    self[:class] = html_class.to_s
  end
end

#environmentize_keys! ⇒ Object

Destructively and non-recursively convert each key to an uppercase string, deleting nil values along the way.

Returns

Hash

The newly environmentized hash.

Examples

{ :name => "Bob", :contact => { :email => "[email protected]" } }.environmentize_keys!
  #=> { "NAME" => "Bob", "CONTACT" => { :email => "[email protected]" } }



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# File 'lib/merb-core/core_ext/hash.rb', line 214

def environmentize_keys!
  keys.each do |key|
    val = delete(key)
    next if val.nil?
    self[key.to_s.upcase] = val
  end
  self
end

#except(*rejected) ⇒ Object

Parameters

*rejected

The hash keys to exclude.

Returns

Hash

A new hash without the selected keys.

Examples

{ :one => 1, :two => 2, :three => 3 }.except(:one)
  #=> { :two => 2, :three => 3 }



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# File 'lib/merb-core/core_ext/hash.rb', line 145

def except(*rejected) 
  reject { |k,v| rejected.include?(k) }
end

#only(*allowed) ⇒ Object

Parameters

*allowed

The hash keys to include.

Returns

Hash

A new hash with only the selected keys.

Examples

{ :one => 1, :two => 2, :three => 3 }.only(:one)
  #=> { :one => 1 }



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# File 'lib/merb-core/core_ext/hash.rb', line 132

def only(*allowed) 
  reject { |k,v| !allowed.include?(k) }
end

#protect_keys! ⇒ Object

Converts all keys into string values. This is used during reloading to prevent problems when classes are no longer declared.

Examples

hash = { One => 1, Two => 2 }.proctect_keys!
hash # => { "One" => 1, "Two" => 2 }



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# File 'lib/merb-core/core_ext/hash.rb', line 188

def protect_keys!
  keys.each {|key| self[key.to_s] = delete(key) }
end

#to_mash ⇒ Object

Returns

Mash

This hash as a Mash for string or symbol key access.



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# File 'lib/merb-core/core_ext/hash.rb', line 79

def to_mash
  hash = Mash.new(self)
  hash.default = default
  hash
end

#to_params ⇒ Object

Returns

String

This hash as a query string

Examples

{ :name => "Bob",
  :address => {
    :street => '111 Ruby Ave.',
    :city => 'Ruby Central',
    :phones => ['111-111-1111', '222-222-2222']
  }
}.to_params
  #=> "name=Bob&address[city]=Ruby Central&address[phones]=111-111-1111222-222-2222&address[street]=111 Ruby Ave."



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# File 'lib/merb-core/core_ext/hash.rb', line 97

def to_params
  params = ''
  stack = []
  
  each do |k, v|
    if v.is_a?(Hash)
      stack << [k,v]
    else
      params << "#{k}=#{v}&"
    end
  end
  
  stack.each do |parent, hash|
    hash.each do |k, v|
      if v.is_a?(Hash)
        stack << ["#{parent}[#{k}]", v]
      else
        params << "#{parent}[#{k}]=#{v}&"
      end
    end
  end
  
  params.chop! # trailing &
  params
end

#to_xml_attributes ⇒ Object Also known as: to_html_attributes

Returns

String

The hash as attributes for an XML tag.

Examples

{ :one => 1, "two"=>"TWO" }.to_xml_attributes
  #=> 'one="1" two="TWO"'



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# File 'lib/merb-core/core_ext/hash.rb', line 155

def to_xml_attributes
  map do |k,v|
    %{#{k.to_s.camel_case.sub(/^(.{1,1})/) { |m| m.downcase }}="#{v}"} 
  end.join(' ')
end

#unprotect_keys! ⇒ Object

Attempts to convert all string keys into Class keys. We run this after reloading to convert protected hashes back into usable hashes.

Examples

# Provided that classes One and Two are declared in this scope:
hash = { "One" => 1, "Two" => 2 }.unproctect_keys!
hash # => { One => 1, Two => 2 }



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# File 'lib/merb-core/core_ext/hash.rb', line 199

def unprotect_keys!
  keys.each do |key| 
    (self[Object.full_const_get(key)] = delete(key)) rescue nil
  end
end