Class: SyntaxTree::YARV::GetConstant

Inherits:
Instruction show all
Defined in:
lib/syntax_tree/yarv/instructions.rb

Overview

### Summary

‘getconstant` performs a constant lookup and pushes the value of the constant onto the stack. It pops both the class it should look in and whether or not it should look globally as well.

### Usage

~~~ruby Constant ~~~

Instance Attribute Summary collapse

Instance Method Summary collapse

Methods inherited from Instruction

#branch_targets, #canonical, #falls_through?, #leaves?, #side_effects?

Constructor Details

#initialize(name) ⇒ GetConstant

Returns a new instance of GetConstant.



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# File 'lib/syntax_tree/yarv/instructions.rb', line 1596

def initialize(name)
  @name = name
end

Instance Attribute Details

#name ⇒ Object (readonly)

Returns the value of attribute name.



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# File 'lib/syntax_tree/yarv/instructions.rb', line 1594

def name
  @name
end

Instance Method Details

#==(other) ⇒ Object 



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# File 'lib/syntax_tree/yarv/instructions.rb', line 1612

def ==(other)
  other.is_a?(GetConstant) && other.name == name
end

#call(vm) ⇒ Object

Raises:

  • (NameError) 


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# File 'lib/syntax_tree/yarv/instructions.rb', line 1628

def call(vm)
  const_base, allow_nil = vm.pop(2)

  if const_base
    if const_base.const_defined?(name)
      vm.push(const_base.const_get(name))
      return
    end
  elsif const_base.nil? && allow_nil
    vm.frame.nesting.reverse_each do |clazz|
      if clazz.const_defined?(name)
        vm.push(clazz.const_get(name))
        return
      end
    end
  end

  raise NameError, "uninitialized constant #{name}"
end

#deconstruct_keys(_keys) ⇒ Object 



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# File 'lib/syntax_tree/yarv/instructions.rb', line 1608

def deconstruct_keys(_keys)
  { name: name }
end

#disasm(fmt) ⇒ Object 



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# File 'lib/syntax_tree/yarv/instructions.rb', line 1600

def disasm(fmt)
  fmt.instruction("getconstant", [fmt.object(name)])
end

#length ⇒ Object 



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# File 'lib/syntax_tree/yarv/instructions.rb', line 1616

def length
  2
end

#pops ⇒ Object 



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# File 'lib/syntax_tree/yarv/instructions.rb', line 1620

def pops
  2
end

#pushes ⇒ Object 



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# File 'lib/syntax_tree/yarv/instructions.rb', line 1624

def pushes
  1
end

#to_a(_iseq) ⇒ Object 



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# File 'lib/syntax_tree/yarv/instructions.rb', line 1604

def to_a(_iseq)
  [:getconstant, name]
end