src/parts.js
function resolveDirectiveValue(directive, part) {
  // Directives are synchronous, so it's safe to read and delete value
  directive(part);
  const value = part._value;
  part._value = undefined;
  return value;
}
function resolveDirectiveValue(directive, part) {
  // Directives are synchronous, so it's safe to read and delete value
  directive(part);
  const value = part._value;
  part._value = undefined;
  return value;
}
function resolveDirectiveValue ( directive , part ) { // Directives are synchronous, so it's safe to read and delete value directive ( part ) ; const value = part . _value ; part . _value = undefined ; return value ; }
Resolve value of "directive"

@param { function } directive
@param { Part } part
@returns { any }
Resolve value of directive