Class: IntNegativeInstruction

Inherits:
Instruction show all
Defined in:
lib/instructions/int/int_negative.rb

Overview

pops the top item of the :int stack; pushes a ValuePoint with the value negated onto the :int stack

needs: 1 :int

pushes: 1 :int

Instance Attribute Summary

Attributes inherited from Instruction

#context

Instance Method Summary collapse

Methods inherited from Instruction

all_instructions, #go, inherited, #initialize, #needs, #pushes, to_nudgecode

Constructor Details

This class inherits a constructor from Instruction

Instance Method Details

#cleanup ⇒ Object 



19
20
21
 
# File 'lib/instructions/int/int_negative.rb', line 19

def cleanup
  pushes :int, @result
end

#derive ⇒ Object 



16
17
18
 
# File 'lib/instructions/int/int_negative.rb', line 16

def derive
    @result = ValuePoint.new("int", -@arg1)
end

#preconditions? ⇒ Boolean

Returns:

  • (Boolean) 


10
11
12
 
# File 'lib/instructions/int/int_negative.rb', line 10

def preconditions?
  needs :int, 1
end

#setup ⇒ Object 



13
14
15
 
# File 'lib/instructions/int/int_negative.rb', line 13

def setup
  @arg1 = @context.pop_value(:int)
end