Class: CodeNthInstruction

Inherits:
Instruction show all
Defined in:
lib/instructions/code/code_nth.rb

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 



21
22
23
 
# File 'lib/instructions/code/code_nth.rb', line 21

def cleanup
  pushes :code, @result
end

#derive ⇒ Object 



10
11
12
13
14
15
16
17
18
19
20
 
# File 'lib/instructions/code/code_nth.rb', line 10

def derive
  tree = NudgeProgram.new(@arg2)
  if tree.linked_code.kind_of?(CodeblockPoint)
    pts = tree[1].contents.length
    raise InstructionMethodError, "#{self.class} can't work on empty blocks" if pts < 1
    val = tree[1].contents[@arg1 % pts]
  else
    val = tree
  end
  @result = ValuePoint.new("code", val.blueprint)
end

#preconditions? ⇒ Boolean

Returns:

  • (Boolean) 


2
3
4
5
 
# File 'lib/instructions/code/code_nth.rb', line 2

def preconditions?
  needs :int, 1
  needs :code, 1
end

#setup ⇒ Object 



6
7
8
9
 
# File 'lib/instructions/code/code_nth.rb', line 6

def setup
  @arg1 = @context.pop_value(:int)
  @arg2 = @context.pop_value(:code)
end