normalize_whitespace( string $str ): string
- Since
- 2.7.0
- Source
wp-includes/formatting.php:5479
Compatibility
- WordPress
- since 2.7.0
- PHP
- 7.4–8.6-dev
- 6.7.7
- 6.8.8
- 6.9.7
- 7.0.4
- 7.1.0
Present in every tracked release (6.7.7 to 7.1.0), and compiles on PHP 7.4 through 8.6-dev.
Parameters
$strstring- The string to normalize.
Return value
string- The normalized string.
Performance profile
How much work a call to normalize_whitespace() does, and what it touches: the algorithmic scaling, the Zend instruction count per call across PHP versions, the hooks it hands control to, and the core code that calls it. Measured from the compiled opcodes, not a stopwatch, so every number is identical on any machine running the same PHP version, and every function in core is ranked by cost.
- Cost class
- Trivial
- Scaling
- Constant
- Instructions
- 10
- Plugin surface
- None
- Called by
- 4
Touches nothing outside its own arguments.
No loop in the body: the same number of instructions runs whatever you pass in.
Executed per call on PHP 8.5. The body compiles to 10.
Nothing here hands control to plugin code.
4 places in core call this, so the cost is paid more often than your own code shows.
What one call costs · 1 distinct outcome
One number would be a lie: the work depends on which branch runs. These are every distinct cost normalize_whitespace() can have, taken from its control-flow graph on PHP 8.5.
| When | Instructions | Calls it makes |
|---|---|---|
| always | 10 | none |
Across PHP versions
| PHP | Compiled | Executed | Branches | Notes |
|---|---|---|---|---|
| 8.6-dev | 10 | 10 | 0 | |
| 8.5 | 10 | 10 | 0 | 1 more instruction than PHP 8.4 |
| 8.4 | 9 | 9 | 0 | 8 fewer instructions than PHP 8.3 |
| 8.3 | 17 | 17 | 0 | |
| 8.2 | 17 | 17 | 0 | |
| 8.1 | 17 | 17 | 0 | |
| 7.4 | 17 | 17 | 0 |
An instruction is not a fixed amount of time, so a matching count is not necessarily the same speed; what it rules out is a difference in the work itself.
Used by · 4
- WP_REST_Autosaves_Controller::create_post_autosave()Creates autosave for the specified post.
- wp_create_post_autosave()Creates autosave data for the specified post from `$_POST` data.
- wp_save_post_revision()Creates a revision for the current version of a post.
- wp_text_diff()Displays a human readable HTML representation of the difference between two strings.
Source code
function normalize_whitespace( $str ) { $str = trim( $str ); $str = str_replace( "\r", "\n", $str ); $str = preg_replace( array( '/\n+/', '/[ \t]+/' ), array( "\n", ' ' ), $str ); return $str;}Changelog
Introduced in 2.7.0. Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
About this page
- Parsed data
- Generated from the wordpress-develop 6.7.7 tag, from
src/wp-includes/formatting.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it. - Corrections
- Something wrong on this page? Report it and it gets fixed in the next regeneration.