Class: Opulent::Context

Inherits:
Object
  • Object
show all
Defined in:
lib/opulent/context.rb

Overview

The context class is used to differentiate local, instance and class variables and to define the current working environment. Each class, method and instance has its own context

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(locals = {}, block = nil, &content) ⇒ Context

Create a context from the environment binding, extended with the locals given as arguments

Parameters:

  • locals (Hash) (defaults to: {}) —

    Binding extension

  • block (Binding) (defaults to: nil) —

    Call environment block

  • content (Binding) —

    Content yielding



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# File 'lib/opulent/context.rb', line 19

def initialize(locals = {}, block = nil, &content)
  @content = content

  @block = block
  if @block
    @binding = @block.binding.clone
  else
    @binding = Binding.new.get
  end

  extend_locals locals
end

Instance Attribute Details

#binding ⇒ Object

Returns the value of attribute binding.



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# File 'lib/opulent/context.rb', line 10

def binding
  @binding
end

#block ⇒ Object

Returns the value of attribute block.



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# File 'lib/opulent/context.rb', line 10

def block
  @block
end

#name ⇒ Object

Returns the value of attribute name.



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# File 'lib/opulent/context.rb', line 10

def name
  @name
end

#parent ⇒ Object

Returns the value of attribute parent.



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# File 'lib/opulent/context.rb', line 10

def parent
  @parent
end

Instance Method Details

#evaluate(code, &block) ⇒ Object

Evaluate ruby code in current context

Parameters:

  • code (String) —

    Code to be evaluated



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# File 'lib/opulent/context.rb', line 36

def evaluate(code, &block)
  begin
    eval code, @binding, &block
  rescue NameError => variable
    Compiler.error :binding, variable, code
  end
end

#evaluate_yield ⇒ Object

Call given input block and return the output



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# File 'lib/opulent/context.rb', line 46

def evaluate_yield
  @content.call if @content
end

#extend_locals(locals) ⇒ Object

Extend the call context with a Hash, String or other Object

Parameters:

  • context (Object) —

    Extension object



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# File 'lib/opulent/context.rb', line 54

def extend_locals(locals)
  # Create new local variables from the input hash
  locals.each do |key, value|
    begin
      @binding.local_variable_set key.to_sym, value
    rescue NameError => variable
      Compiler.error :variable_name, variable, key
    end
  end
end

#extend_nonlocals(bind) ⇒ Object

Extend instance, class and global variables for use in definitions

Parameters:

  • bind (Binding) —

    Binding to extend current context binding



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# File 'lib/opulent/context.rb', line 69

def extend_nonlocals(bind)
  bind.eval('instance_variables').each do |var|
    @binding.eval('self').instance_variable_set var, bind.eval(var.to_s)
  end

  bind.eval('self.class.class_variables').each do |var|
    @binding.eval('self').class_variable_set var, bind.eval(var.to_s)
  end
end