try and catch

Handle a parsing failure with a fallback label.

try_catch_parse.js

const text = "42";
let label = "";

try {
  const value = Number(text);
  if (Number.isNaN(value)) {
    throw new Error("not numeric");
  }
  label = "value:" + value;
} catch (error) {
  label = "fallback";
}

console.log("text=" + text);
console.log("label=" + label);

try-catch-parse `try` runs code that may fail. `catch` handles the failure and lets the program continue with a fallback value.