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<?php echo preg_replace('/\//', '\\\\', "Using 4 slashes: a / b\n"); echo preg_replace('/\//', '\\\\\\\\', "Using 8 slashes: a / b\n");
Output for 5.6.0 - 5.6.38, 7.0.0 - 7.0.33, 7.1.0 - 7.1.25, 7.2.0 - 7.2.33, 7.3.0 - 7.3.26, 7.4.0 - 7.4.14, 8.0.0
Using 4 slashes: a \ b Using 8 slashes: a \\ b