Class: ExecKInstruction

Inherits:
Instruction show all
Defined in:
lib/instructions/exec/exec_k.rb

Overview

Implements the K Combinator on the :exec stack: deletes the second item (replacing the top one).

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 



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# File 'lib/instructions/exec/exec_k.rb', line 15

def cleanup
  pushes :exec, @keep
end

#derive ⇒ Object 



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# File 'lib/instructions/exec/exec_k.rb', line 13

def derive
end

#preconditions? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/instructions/exec/exec_k.rb', line 6

def preconditions?
  needs :exec, 2
end

#setup ⇒ Object 



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# File 'lib/instructions/exec/exec_k.rb', line 9

def setup
  @keep = @context.pop(:exec)
  @discard = @context.pop(:exec)
end