Re: RFC: blank() Function as a Complement to empty()

On Sat, Apr 5, 2025, at 14:15, Kayck Matias wrote: > *INTRODUCTION* > This RFC proposes the addition of a new global function blank() > to PHP’s core, intended to provide a more intuitive and context-sensitive way of checking for > "blank" values. This function is *not a replacement* for > empty(), but a *complementary tool *to help developers more > accurately evaluate user input, query parameters, and form values — particularly in situations > where empty() may behave in unintuitive ways. > > > *MOTIVATION *The motivation for this RFC arose from a real-world issue I encountered at work involving query string filtering — specifically when using the string "0" as a filter value. Because empty("0") evaluates to true, the logic skipped this valid input, causing incorrect behavior in the application. This highlighted a gap in PHP’s current toolset for handling “blank” values in a more semantic and intention-aligned way. I would personally advocate that empty() NEVER be used on strings. There are too many edge cases. As I said in an earlier message on the thread, if you want to know if a string is empty, just do $string == "" -- note the double equals, not triple equals. This matches null, an actual empty string, and false, but won't match anything else. > *PROPOSAL* > The proposed blank() function will behave similarly to > empty(), but with semantics better suited for filtering, validation, > and user input.. Its primary goals are: > • To treat whitespace-only strings as blank (e.g., " > "). > > • To treat "0" (string zero) and > 0 (int zero) as *not blank*, unlike �Uo�g|� > "XO��ֳempty(). > > • To support clearer, intention-driven logic when working with dynamic input, especially in > query strings and HTTP forms. > > Function Signature > > function blank(mixed $value): bool; > ** > Logic (PHP version) > function blank(mixed $value): bool > { > if ( > false === $value || > (empty($value) && '0' != $value) || > (\is_string($value) && '' === \trim($value)) > ) { > return true; > } > > return false; > } > Examples > echo blank(null); // true > echo blank(false); // true > echo blank(""); // true > echo blank(" "); // true > echo blank([]); // true > > echo blank(0); // false > echo blank("0"); // false > echo blank("test"); // false > echo blank([0]); // false I agree with most of these. I do not agree that " " (a space) is blank though. For people without last names, this is often their last name to pass validation on forms. As I said earlier, a simple loose check with an empty string is usually all you need, not empty(). > Best Regards, > Kayck Matias ☕ — Rob