Prefix and Suffix Functions

The main vote failed 11 to 8, with 7 abstaining, short of the two-thirds majority it needed. The second vote, on parameter order, picked "Last" 16 to 7, with 1 abstaining, though that only mattered if the main vote passed. An earlier vote was cancelled in February 2026 to add the parameter order question. Voting closed on March 13, 2026.

A lot of PHP code adds or strips a piece at the start or end of a string, usually by checking with str_starts_with() and then cutting with substr(). It works, but it's wordy and easy to get a length wrong. This RFC from Carlos Granados proposed six small functions that do each job in one call. It was declined.

The six functions#

There are three pairs, each with a prefix version and a suffix version:

• str_prefix_ensure() and str_suffix_ensure() add the text only if it's missing.
• str_prefix_remove() and str_suffix_remove() remove the text only if it's there.
• str_prefix_replace() and str_suffix_replace() swap it for new text only if it's there.

Here is the before and after, using the RFC's own examples:

// Before
if (str_starts_with($host, 'www.')) {
    $host = substr($host, strlen('www.'));
}

// After
$host = str_prefix_remove($host, 'www.');           // "example.com"
$file = str_suffix_replace('.jpeg', '.jpg', $file); // "photo.jpg"
$key  = str_prefix_ensure($key, 'app:');            // "app:user:123"

How they behave#

• They always return a string, never false.
• If nothing matches, you get the original string back with no warning.
• Matching is exact and case-sensitive, so .jpeg won't match .JPEG.
• They only look at the very start or end, and only once. str_suffix_remove("path///", "/") returns "path//".
• They don't know anything about URLs or file paths. They just compare bytes.

An empty prefix or suffix is a special case. For the _replace functions it always matches, so the new text is always added.

Parameter order#

People disagreed about where $subject should go in the two _replace functions. The RFC put it last, matching str_replace(), while the other four functions take it first. A second vote let voters choose.

What it means for existing code#

Nothing breaks. These are six new global functions, so your code would only clash if you already defined functions with these exact names. The RFC says a GitHub search found none.