Special value to ignore entry

Thanks for a very useful module!

I’m writing a fairly complex XML-generation program and there are cases where some attributes/elements may or may not be included, depending on the business logic. Right now, in order to ignore such an entry, I need to add an explicit condition that only adds the entry in case the condition is satisfied.

A simpler way to code would be to add the entry regardless, and reserve a special value, e.g. undefined, to instruct the XML generator to ignore the entry when the special value is found.

For example, instead of writing:

const snippet = [{
  'element1': 'hello',
}];
if (condition) {
  snippet.push({ 'element2': 'goodbye' });
}

one could write:

const snippet = [{
   'element1': 'hello'
}, {
   'element2': condition ? 'goodbye' : undefined
}];

[infojunkie]

That worked great! Thank you.

[davidcalhoun]

I think I see what you’re saying. You can do this in JS like this:

// Positive condition:
toXML([
    {
        element1: 'hello'
    },
    {
        ...(true && {
            element2: 'goodbye'
        })
    }
]);
// -> '<element1>hello</element1><element2>goodbye</element2>'

// Negative condition:
toXML([
    {
        element1: 'hello'
    },
    {
        ...(false && {
            element2: 'goodbye'
        })
    }
]);
// -> '<element1>hello</element1>'