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function is not described

WP_Http_Encoding::decompress() public WP 2.8.0

Decompression of deflated string.

Will attempt to decompress using the RFC 1950 standard, and if that fails then the RFC 1951 standard deflate will be attempted. Finally, the RFC
1952 standard gzip decode will be attempted. If all fail, then the original compressed string will be returned.

{} It's a method of the class: WP_Http_Encoding{}

No Hooks.

Return

String|false. Decompressed string on success, false on failure.

Usage

$result = WP_Http_Encoding::decompress( $compressed, $length );
$compressed(string) (required)
String to decompress.
$length(int)
The optional length of the compressed data.

Changelog

Since 2.8.0 Introduced.

Code of WP_Http_Encoding::decompress() WP 5.7.1

<?php
public static function decompress( $compressed, $length = null ) {

	if ( empty( $compressed ) ) {
		return $compressed;
	}

	$decompressed = @gzinflate( $compressed );
	if ( false !== $decompressed ) {
		return $decompressed;
	}

	$decompressed = self::compatible_gzinflate( $compressed );
	if ( false !== $decompressed ) {
		return $decompressed;
	}

	$decompressed = @gzuncompress( $compressed );
	if ( false !== $decompressed ) {
		return $decompressed;
	}

	if ( function_exists( 'gzdecode' ) ) {
		$decompressed = @gzdecode( $compressed );

		if ( false !== $decompressed ) {
			return $decompressed;
		}
	}

	return $compressed;
}