Trying robot to convert more to TS

ember-apache-echarts/src/helpers/coalesce.ts

@@ -3,12 +3,7 @@ import { helper } from '@ember/component/helper';
 /**
  * Returns the first non-null defined value from the positional parameters, or
  * `undefined` if no non-null values were passed in.
- *
- * @param {array} positional - The positional parameters for this function
- *
- * @return {any} The first non-null defined element of `positional` or
- *               `undefined` if all the elements are null or undefined
  */
-export default helper(function coalesce(positional) {
+export default helper(function coalesce(positional: unknown[]): unknown {
   return positional.find((param) => param != null);
 });

ember-apache-echarts/src/helpers/css-size.ts

@@ -2,22 +2,14 @@ import { helper } from '@ember/component/helper';
 
 const numberRegEx = /^\d+$/;
 
-const isNumeric = (value: unknown) =>
+const isNumeric = (value: unknown): boolean =>
   typeof value === 'number' || (typeof value === 'string' && value.match(numberRegEx) != null);
 
 /**
  * Formats a value so it can be used as a size in CSS expressions. Automatically
  * uses `px` as the unit for nummeric values.
- *
- * @param {array} positional - The positional parameters for this function
- * @param {string|number} positional[0] - The value to format as a CSS size
- * @param {string|number} positional[1] - The default value if the value is null
- *                                        or undefined
- *
- * @return {string} The value formatted as a CSS size
  */
-
-export default helper(function cssSize(positional: [string?, string?] /*, named*/): string {
+export default helper(function cssSize(positional: [string?, string?]): string {
   const size = positional[0] != null && positional[0] !== '' ? positional[0] : positional[1];
 
   return isNumeric(size) || size === ''