Editorial: use abstract closures in MakeArg{Getter,Setter} (tc39#2439)

spec.html

@@ -12108,46 +12108,24 @@ <h1>CreateMappedArgumentsObject ( _func_, _formals_, _argumentsList_, _env_ )</h
           <h1>MakeArgGetter ( _name_, _env_ )</h1>
           <p>The abstract operation MakeArgGetter takes arguments _name_ (a String) and _env_ (an Environment Record). It creates a built-in function object that when executed returns the value bound for _name_ in _env_. It performs the following steps when called:</p>
           <emu-alg>
-            1. Let _steps_ be the steps of an ArgGetter function as specified below.
-            1. Let _length_ be the number of non-optional parameters of an ArgGetter function as specified below.
-            1. Let _getter_ be ! CreateBuiltinFunction(_steps_, _length_, *""*, &laquo; [[Name]], [[Env]] &raquo;).
-            1. Set _getter_.[[Name]] to _name_.
-            1. Set _getter_.[[Env]] to _env_.
+            1. Let _getterClosure_ be a new Abstract Closure with no parameters that captures _name_ and _env_ and performs the following steps when called:
+              1. Return _env_.GetBindingValue(_name_, *false*).
+            1. Let _getter_ be ! CreateBuiltinFunction(_getterClosure_, 0, *""*, &laquo; &raquo;).
+            1. NOTE: _getter_ is never directly accessible to ECMAScript code.
             1. Return _getter_.
           </emu-alg>
-          <p>An ArgGetter function is an anonymous built-in function with [[Name]] and [[Env]] internal slots. When an ArgGetter function that expects no arguments is called it performs the following steps:</p>
-          <emu-alg>
-            1. Let _f_ be the active function object.
-            1. Let _name_ be _f_.[[Name]].
-            1. Let _env_ be _f_.[[Env]].
-            1. Return _env_.GetBindingValue(_name_, *false*).
-          </emu-alg>
-          <emu-note>
-            <p>ArgGetter functions are never directly accessible to ECMAScript code.</p>
-          </emu-note>
         </emu-clause>
 
         <emu-clause id="sec-makeargsetter" aoid="MakeArgSetter">
           <h1>MakeArgSetter ( _name_, _env_ )</h1>
           <p>The abstract operation MakeArgSetter takes arguments _name_ (a String) and _env_ (an Environment Record). It creates a built-in function object that when executed sets the value bound for _name_ in _env_. It performs the following steps when called:</p>
           <emu-alg>
-            1. Let _steps_ be the steps of an ArgSetter function as specified below.
-            1. Let _length_ be the number of non-optional parameters of an ArgSetter function as specified below.
-            1. Let _setter_ be ! CreateBuiltinFunction(_steps_, _length_, *""*, &laquo; [[Name]], [[Env]] &raquo;).
-            1. Set _setter_.[[Name]] to _name_.
-            1. Set _setter_.[[Env]] to _env_.
+            1. Let _setterClosure_ be a new Abstract Closure with parameters (_value_) that captures _name_ and _env_ and performs the following steps when called:
+              1. Return _env_.SetMutableBinding(_name_, _value_, *false*).
+            1. Let _setter_ be ! CreateBuiltinFunction(_setterClosure_, 1, *""*, &laquo; &raquo;).
+            1. NOTE: _setter_ is never directly accessible to ECMAScript code.
             1. Return _setter_.
           </emu-alg>
-          <p>An ArgSetter function is an anonymous built-in function with [[Name]] and [[Env]] internal slots. When an ArgSetter function is called with argument _value_ it performs the following steps:</p>
-          <emu-alg>
-            1. Let _f_ be the active function object.
-            1. Let _name_ be _f_.[[Name]].
-            1. Let _env_ be _f_.[[Env]].
-            1. Return _env_.SetMutableBinding(_name_, _value_, *false*).
-          </emu-alg>
-          <emu-note>
-            <p>ArgSetter functions are never directly accessible to ECMAScript code.</p>
-          </emu-note>
         </emu-clause>
       </emu-clause>
     </emu-clause>