diff --git a/common/web/types/src/kmx/element-string.ts b/common/web/types/src/kmx/element-string.ts
index 816627c3d3..ebf4d398e5 100644
--- a/common/web/types/src/kmx/element-string.ts
+++ b/common/web/types/src/kmx/element-string.ts
@@ -31,11 +31,11 @@ export class ElementString extends Array<ElemElement> {
    * @param source if a string array, does not get reinterpreted as UnicodeSet. This is used with vars, etc. Or pass `["str"]` for an explicit 1-element elem.
    * If it is a string, will be interpreted per reorder element rules.
    */
-  constructor(sections: DependencySections, source: string | string[], order?: string, tertiary?: string, tertiary_base?: string, prebase?: string) {
-    super();
-    //TODO-LDML: full UnicodeSet and parsing
+  static fromStrings(sections: DependencySections, source: string | string[], order?: string, tertiary?: string, tertiary_base?: string, prebase?: string) : ElementString {
+    // the returned array
+    const array = new ElementString();
     if(!source) {
-      return;
+      return array;
     }
 
     let items : ElementSegment[];
@@ -104,8 +104,9 @@ export class ElementString extends Array<ElemElement> {
         (ElemElementFlags.type & typeFlag) |
         (tertiary_bases?.[i] == '1' /* TODO-LDML: or 'true'? */ ? ElemElementFlags.tertiary_base : 0) |
         (prebases?.[i] == '1' /* TODO-LDML: or 'true'? */ ? ElemElementFlags.prebase : 0);
-      this.push(elem);
+      array.push(elem);
     };
+    return array;
   }
   isEqual(a: ElementString): boolean {
     if (a.length != this.length) {
diff --git a/common/web/types/src/kmx/kmx-plus.ts b/common/web/types/src/kmx/kmx-plus.ts
index d28bcbfd3f..1060e50fba 100644
--- a/common/web/types/src/kmx/kmx-plus.ts
+++ b/common/web/types/src/kmx/kmx-plus.ts
@@ -35,14 +35,14 @@ export class Elem extends Section {
   strings: ElementString[] = [];
   constructor(sections: DependencySections) {
     super();
-    this.strings.push(new ElementString(sections, '')); // C7043: null element string
+    this.strings.push(ElementString.fromStrings(sections, '')); // C7043: null element string
   }
   /**
    * @param source if a string array, does not get reinterpreted as UnicodeSet. This is used with vars, etc. Or pass `["str"]` for an explicit 1-element elem.
    * If it is a string, will be interpreted per reorder element ruls.
    */
   allocElementString(sections: DependencySections, source: string | string[], order?: string, tertiary?: string, tertiary_base?: string, prebase?: string): ElementString {
-    let s = new ElementString(sections, source, order, tertiary, tertiary_base, prebase);
+    let s = ElementString.fromStrings(sections, source, order, tertiary, tertiary_base, prebase);
     let result = this.strings.find(item => item.isEqual(s));
     if(result === undefined) {
       result = s;
@@ -547,14 +547,14 @@ export class List extends Section {
     let result = this.lists.find(item => item.isEqual(s));
     if(result === undefined) {
       // allocate a new ListItem
-      result = new ListItem(s, opts, sections);
+      result = ListItem.fromStrings(s, opts, sections);
       this.lists.push(result);
     }
     return result;
   }
   constructor(strs: Strs) {
     super();
-    this.lists.push(new ListItem([], {}, { strs })); // C7043: null element string
+    this.lists.push(ListItem.fromStrings([], {}, { strs })); // C7043: null element string
   }
   lists: ListItem[] = [];
 };
diff --git a/common/web/types/src/kmx/string-list.ts b/common/web/types/src/kmx/string-list.ts
index 2e313dae0c..411c940acf 100644
--- a/common/web/types/src/kmx/string-list.ts
+++ b/common/web/types/src/kmx/string-list.ts
@@ -33,15 +33,16 @@ export class ListItem extends Array<ListIndex> implements OrderedStringList {
    * be needed depending on the options
    * @returns
    */
-  constructor(source: Array<string>, opts: StrsOptions, sections: DependencySections) {
-    super();
-    if(!source) {
-      return;
+  static fromStrings(source: Array<string>, opts: StrsOptions, sections: DependencySections) : ListItem {
+    const a = new ListItem();
+    if (!source) {
+      return a;
     }
     for (const str of source) {
         let index = new ListIndex(sections.strs.allocString(str, opts, sections));
-        this.push(index);
+        a.push(index);
     }
+    return a;
   }
   getItemOrder(item: string): number {
     return this.findIndex(({value}) => value.value === item);