ResultElement : add ordered keys() getter

src/util/resultelement.ts

@@ -47,23 +47,6 @@ export class ResultElement {
      *          for ex. with SectionParametree
      */
     get vCalc(): number {
-        /* if (this.parent && this.parent.symbol) {
-            if (this.parent.symbol in this._values) {
-                return this._values[this.parent.symbol];
-            } else {
-                // required symbol not found; if only the empty key "" is present,
-                // return its value (@WARNING clodo rustine)
-                if (this.count() > 1) {
-                    // throw new Error("clodo rustine failed");
-                    return undefined;
-                } else {
-                    return this.firstValue;
-                }
-            }
-        }
-        // default retrocompatible pseudo-symbol for cases like  `new ResultElement(42);`
-        return this._values[""]; */
-
         return this._values[this.vCalcSymbol];
     }
 
@@ -99,6 +82,24 @@ export class ResultElement {
         this._values = { ...this._values, ...values };
     }
 
+    /**
+     * Returns an array of all the keys in the local values map,
+     * where vCalcSymbol is always in first position (used by
+     * GUI to iterate on displayable results)
+     */
+    public get keys(): string[] {
+        const keys = Object.keys(this._values);
+        //  make sure vCalc symbol is always first
+        if (this.vCalcSymbol) { // sometimes empty (ex: SectionParametree)
+            const index = keys.indexOf(this.vCalcSymbol);
+            if (index > -1) {
+                keys.splice(index, 1);
+            }
+            keys.unshift(this.vCalcSymbol);
+        }
+        return keys;
+    }
+
     /**
      * @returns the result value associated to the given symbol, or undefined if the given
      *          symbol was not found in the local values map