[Feature Request] treat undefined keys as false

[lexey111]

Hi! Thank you very much for the loader, it is very useful.

It would be very nice to add one minor feature to it - some option in config to treat "absent" (or unset) keys as "false".

[nippur72]

but if they are absent, how do you know their names in order to turn them into false?

[lexey111]

Like this (dirty patch) -

preprocessor.ts

function evaluate(condition: string, defs: OptionObject): boolean {
   const code = `return (${condition}) ? true : false;`;
   const args = Object.keys(defs);

   let result: boolean;
   try {
     const f = new Function(...args, code);
     result = f(...args.map((k) => defs[k]));
      //console.log(`evaluation of (${condition}) === ${result}`);
   }
   catch(error) {
      // throw `error evaluation #if condition(${condition}): ${error}`;
      return false; // ...if option "treatAbsentAsFalse" is set and error is ReferenceError
   }

   return result;
}