class Glimmer::DSL::Expression

Represents a Glimmer DSL expression (e.g. label(:center) { … })

An expression object can interpret a keyword, args, and a block into a UI object

Expressions subclasses follow the convention of using ‘and` and `or` english versino of Ruby’s boolean operations. This allows easy DSL-like readability of the rules, and easy printout with puts_debuggerer when troubleshooting.

Public Class Methods

dsl() click to toggle source
# File lib/glimmer/dsl/expression.rb, line 35
def dsl
  @dsl ||= name.split(/::/)[-2].downcase.to_sym
end

Public Instance Methods

add_content(new_parent, keyword, *args, &block) click to toggle source

Adds block content to newly interpreted parent object (Optional)

Only expressions that receive a content block should implement

# File lib/glimmer/dsl/expression.rb, line 53
def add_content(new_parent, keyword, *args, &block)
  # No Op by default
end
around(parent, keyword, args, block, &interpret_and_add_content) click to toggle source

Executes code around the ‘interpret_and_add_content` block, which invokes `interpret` and `add_content` when called without args (parent, keyword, args, block are supplied automatically). Clients may invoke yield as an alternative to calling `interpret_and_add_content` directly. This method takes parent, keyword, args, block in case they are needed in its around logic.

# File lib/glimmer/dsl/expression.rb, line 63
def around(parent, keyword, args, block, &interpret_and_add_content)
  interpret_and_add_content.call
end
can_interpret?(parent, keyword, *args, &block) click to toggle source

Checks if it can interpret parameters (subclass must override)

# File lib/glimmer/dsl/expression.rb, line 41
def can_interpret?(parent, keyword, *args, &block)
  raise Error, "#can_interpret? must be implemented by an Expression subclass"
end
interpret(parent, keyword, *args, &block) click to toggle source

Interprets parameters (subclass must override)

# File lib/glimmer/dsl/expression.rb, line 46
def interpret(parent, keyword, *args, &block)
  raise Error, "#interpret must be implemented by an Expression subclass"
end
textual?(object) click to toggle source

Checks if object is a Symbol or a String

# File lib/glimmer/dsl/expression.rb, line 68
def textual?(object)
  object.is_a?(Symbol) or object.is_a?(String)
end