module ActionController
module Sass
module Sass::CacheStores
module Sass::Callbacks
module Sass::Callbacks::InstanceMethods
module Sass::Exec
module Sass::Features
module Sass::Importers
module Sass::Logger
module Sass::Logger::LogLevel
module Sass::Logger::LogLevel::ClassMethods
module Sass::Media
module Sass::Plugin
module Sass::Plugin::Configuration
module Sass::SCSS
module Sass::SCSS::RX
module Sass::Script
module Sass::Script::Functions
module Sass::Script::Tree
module Sass::Script::Value
module Sass::Script::Value::Helpers
module Sass::Selector
module Sass::Shared
module Sass::Source
module Sass::Supports
module Sass::Tree
module Sass::Tree::Visitors
module Sass::Util
module Sass::Util::Test
module Sass::Version
class ActionController::Base
class Sass::BaseEnvironment
class Sass::CSS
class Sass::CacheStores::Base
class Sass::CacheStores::Chain
class Sass::CacheStores::Filesystem
class Sass::CacheStores::Memory
class Sass::CacheStores::Null
class Sass::Deprecation
class Sass::Engine
class Sass::Engine::Line
class Sass::Environment
class Sass::Exec::Base
class Sass::Exec::SassConvert
class Sass::Exec::SassScss
class Sass::Importers::Base
class Sass::Importers::DeprecatedPath
class Sass::Importers::Filesystem
class Sass::Logger::Base
class Sass::Logger::Delayed
class Sass::Media::Query
class Sass::Media::QueryList
class Sass::Plugin::Compiler
class Sass::Plugin::MerbBootLoader
class Sass::Plugin::Rack
class Sass::Plugin::StalenessChecker
class Sass::ReadOnlyEnvironment
class Sass::Repl
class Sass::SCSS::CssParser
class Sass::SCSS::Parser
class Sass::SCSS::StaticParser
class Sass::Script::CssLexer
class Sass::Script::CssParser
class Sass::Script::Functions::EvaluationContext
class Sass::Script::Lexer
class Sass::Script::Parser
class Sass::Script::Tree::Funcall
class Sass::Script::Tree::Interpolation
class Sass::Script::Tree::ListLiteral
class Sass::Script::Tree::Literal
class Sass::Script::Tree::MapLiteral
class Sass::Script::Tree::Node
class Sass::Script::Tree::Operation
class Sass::Script::Tree::Selector
class Sass::Script::Tree::StringInterpolation
class Sass::Script::Tree::UnaryOperation
class Sass::Script::Tree::Variable
class Sass::Script::Value::ArgList
class Sass::Script::Value::Base
class Sass::Script::Value::Bool
class Sass::Script::Value::Callable
class Sass::Script::Value::Color
class Sass::Script::Value::Function
class Sass::Script::Value::List
class Sass::Script::Value::Map
class Sass::Script::Value::Null
class Sass::Script::Value::Number
class Sass::Script::Value::String
class Sass::Selector::AbstractSequence
class Sass::Selector::Attribute
class Sass::Selector::Class
class Sass::Selector::CommaSequence
class Sass::Selector::Element
class Sass::Selector::Id
class Sass::Selector::Parent
class Sass::Selector::Placeholder
class Sass::Selector::Pseudo
class Sass::Selector::Sequence
class Sass::Selector::Simple
class Sass::Selector::SimpleSequence
class Sass::Selector::Universal
class Sass::SemiGlobalEnvironment
class Sass::Source::Map
class Sass::Source::Map::Mapping
class Sass::Source::Position
class Sass::Source::Range
class Sass::Stack
class Sass::Stack::Frame
class Sass::Supports::Condition
class Sass::Supports::Declaration
class Sass::Supports::Interpolation
class Sass::Supports::Negation
class Sass::Supports::Operator
class Sass::SyntaxError
class Sass::Tree::AtRootNode
class Sass::Tree::CharsetNode
class Sass::Tree::CommentNode
class Sass::Tree::ContentNode
class Sass::Tree::CssImportNode
class Sass::Tree::DebugNode
class Sass::Tree::DirectiveNode
class Sass::Tree::EachNode
class Sass::Tree::ErrorNode
class Sass::Tree::ExtendNode
class Sass::Tree::ForNode
class Sass::Tree::FunctionNode
class Sass::Tree::IfNode
class Sass::Tree::ImportNode
class Sass::Tree::KeyframeRuleNode
class Sass::Tree::MediaNode
class Sass::Tree::MixinDefNode
class Sass::Tree::MixinNode
class Sass::Tree::Node
class Sass::Tree::PropNode
class Sass::Tree::ReturnNode
class Sass::Tree::RootNode
class Sass::Tree::RuleNode
class Sass::Tree::SupportsNode
class Sass::Tree::TraceNode
class Sass::Tree::VariableNode
class Sass::Tree::Visitors::Base
class Sass::Tree::Visitors::CheckNesting
class Sass::Tree::Visitors::Convert
class Sass::Tree::Visitors::Cssize
class Sass::Tree::Visitors::Cssize::Bubble
class Sass::Tree::Visitors::DeepCopy
class Sass::Tree::Visitors::Extend
class Sass::Tree::Visitors::Perform
class Sass::Tree::Visitors::SetOptions
class Sass::Tree::Visitors::ToCss
class Sass::Tree::WarnNode
class Sass::Tree::WhileNode
class Sass::UnitConversionError
class Sass::Util::MultibyteStringScanner
class Sass::Util::NormalizedMap
class Sass::Util::StaticConditionalContext
class Sass::Util::SubsetMap
sass
3.7.4
# optional?
(Boolean)
def optional?; @optional; end