Class: Opal::Nodes::IFlipFlop

Inherits:
Base
  • Object
show all
Defined in:
opal/lib/opal/nodes/if.rb

Direct Known Subclasses

EFlipFlop

Instance Attribute Summary

Attributes inherited from Base

#compiler, #sexp, #type

Instance Method Summary collapse

Methods inherited from Base

#add_gvar, #add_ivar, #add_local, #add_temp, #children, children, #class_variable_owner, #class_variable_owner_nesting_level, #comments, #compile_to_fragments, #error, #expr, #expr?, #expr_or_nil, #fragment, handle, handlers, #has_rescue_else?, #helper, #in_ensure, #in_ensure?, #in_resbody, #in_resbody?, #in_rescue, #in_while?, #initialize, #process, #push, #recv, #recv?, #s, #scope, #source_location, #stmt, #stmt?, #top_scope, truthy_optimize?, #unshift, #while_loop, #with_temp, #wrap

Methods included from Helpers

#current_indent, #empty_line, #indent, #js_truthy, #js_truthy_optimize, #line, #mid_to_jsid, #property, #valid_name?

Constructor Details

This class inherits a constructor from Opal::Nodes::Base

Instance Method Details

#compile ⇒ Object

We create a function that we put in the top scope, that stores the state of our flip-flop. We pass to it functions that are ran with the current binding.



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# File 'opal/lib/opal/nodes/if.rb', line 397

def compile
  helper :truthy

  fun_name = top_scope.new_temp
  ff = "#{fun_name}.$$ff"

  push "(typeof #{fun_name} === 'undefined' ? (#{fun_name} = function(from, to){"
  push "  if (typeof #{ff} === 'undefined') #{ff} = false;"
  push "  var retval = #{ff};"
  push "  if (!#{ff}) {"
  push "    #{ff} = retval = $truthy(from());"
  push "  }"
  push "  #{excl}if (#{ff}) {"
  push "    if ($truthy(to())) #{ff} = false;"
  push "  }"
  push "  return retval;"
  push "}) : #{fun_name})("
  push "  function() { ", stmt(compiler.returns(from)), " },"
  push "  function() { ", stmt(compiler.returns(to)), " }"
  push ")"
end

#excl ⇒ Object

Is this an exclusive flip flop? If no, run both branches



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# File 'opal/lib/opal/nodes/if.rb', line 391

def excl
  ""
end