Define an AO for creating Decimal.Amount objects

Author: jessealama

spec.emu

@@ -412,6 +412,31 @@ location: https://github.com/tc39/proposal-decimal/
         <p>Decimal.Amount values are intended to contain a Decimal value together with a precision, as well as information about how the precision that number should be understood. The two ways precision can be understood are in terms of fractional digits and significant digits.</p>
       </emu-intro>
 
+      <emu-clause id="sec-decimal-amount-abstract-ops">
+        <h1>Abstract Operations</h1>
+        <emu-clause id="sec-decimal-amount-create-decimal-armount" type="abstract operation">
+          <h1>
+            CreateDecimalAmount (
+              _value_ : a Decimal value,
+              _digits_ : a mathematical value
+            ): a Decimal.Amount object
+          </h1>
+          <dl class="header">
+            <dt>description</dt>
+            <dd>It creates a Decimal.Amount object having the given value with the given number of significant digits.</dd>
+          </dl>
+          <emu-alg>
+            1. Assert: _digits_ is an integer.
+            1. Assert: 0 ≤ _digits_.
+            1. Assert: _digits_ ≤ 34.
+            1. Let _O_ be ! OrdinaryCreateFromConstructor(%DecimalAmount%, *"%DecimalAmount.prototype%"*, « [[DecimalAmountData]], [[DecimalAmountSignificantDigits]] »).
+            1. Set _O_.[[DecimalAmountData]] to _value_.
+            1. Set _O_.[[DecimalAmountSignificantDigits]] to _digits_.
+            1. Return _O_.
+          </emu-alg>
+        </emu-clause>
+      </emu-clause>
+
       <emu-clause id="sec-the-decimal-amount-constructor">
         <h1>The Decimal.Amount Constructor</h1>
         <p>The Decimal.Amount constructor:</p>
@@ -432,10 +457,7 @@ location: https://github.com/tc39/proposal-decimal/
             1. If ℝ(_precision_) is not an integer, throw a *RangeError* exception.
             1. If ℝ(_precision_) > 34, throw a *RangeError* exception.
             1. Let _decimal_ be ? Construct(%Decimal%, _s_).
-            1. Let _O_ be ? OrdinaryCreateFromConstructor(NewTarget, *"%DecimalAmount.prototype%"*, « [[DecimalAmountData]], [[DecimalAmountSignificantDigits]] »).
-            1. Set _O_.[[DecimalAmountData]] to _decimal_.[[DecimalData]].
-            1. Set _O_.[[DecimalAmountSignificantDigits]] to _precision_.
-            1. Return _O_.
+            1. Return CreateDecimalAmount (_decimal_.[[DecimalData]], ℝ(_precision_)).
           </emu-alg>
         </emu-clause>
       </emu-clause>
@@ -1120,11 +1142,10 @@ location: https://github.com/tc39/proposal-decimal/
       1. Let _d_ be _O_.[[DecimalData]].
       1. Assert: _d_ is a mathematical value.
       1. If _d_ = 0, return ? Construct(%DecimalAmount%, « *"0", _n_ * »).
-      1. Let _s_ be DecimalToDecimalString(_d_).
       1. Let _l_ be log-10 of |_d_|.
       1. Let _numIntegerDigits_ be _l_ + 1.
       1. Let _newPrecision_ be _numIntegerDigits_ - ℝ(_n_).
-      1. Return ? Construct(%DecimalAmount%, « _s_, 𝔽(_newPrecision_) »).
+      1. Return CreateDecimalAmount(_d_, _newPrecision_).
     </emu-alg>
   </emu-clause>
 
@@ -1135,9 +1156,12 @@ location: https://github.com/tc39/proposal-decimal/
     <emu-alg>
       1. Let _O_ be the *this* value.
       1. Perform ? RequireInternalSlot(_O_, [[DecimalData]]).
+      1. If _n_ is not a Number, throw a *TypeError* exception.
+      1. If ℝ(_n_) < 0, throw a *RangeError* exception.
+      1. If ℝ(_n_) is not an integer, throw a *RangeError* exception.
+      1. If ℝ(_n_) > 34, throw a *RangeError* exception.
       1. Let _d_ be _O_.[[DecimalData]].
-      1. Let _s_ be DecimalToDecimalString(_d_).
-      1. Return ? Construct(%DecimalAmount%, « _s_, _n_ »).
+      1. Return CreateDecimalAmount(_d_, ℝ(_n_)).
     </emu-alg>
   </emu-clause>