do you think i should keep all my php functions in one file?

i was wondering do you think i should keep all my functions in one file, or seperate them in different files!!

p.s if i put all the functions in one file, would it be easier for php to process that stuff!!

It depends on how many functions they are, how long they are, and what they do. For any significant project, putting everything in one file is generally a bad idea. They should be categorized by what they do.

Having things in separate files is important not only for organization and legibility, but it also really helps during source control to see that a certain file has changed but all the others have stayed the same.

According to my experience, the fewer files you include the faster a PHP script runs. If separating the functions in several files means you need to use include or require several times, it's probably best to keep the functions in one file.

This is premature optimization attempt. The time for processing of the actual file content is going to outweigh the time saved in opening one closing the files. So you are saving maybe 0.01% of the time by splitting the files.

For a very large project, the loss in speed will be made up by the gain in modularity, and if done correctly, scalability. This function is very simple, very small, and can be used to include any php and then execute it, without the need for a long if() else or switch case. Now, this may be more intensive then a switch case statement, but for a large project this function is perfect.

function trnFeature_getFeature($feature = 'default', $options = array()) {
    
    $path = __DIR__ . "/features/{$feature}/{$feature}";
    
    //Check the path, if no file exists bail out
    if(!file_exists($path . '.php')) {
      return false;
    }
  
    //The path checked out, include the file
    include_once $path . '.php';
    
    //setup the function that will execute the feature
    $feature_fn = "trnFeature_" . $feature . "_featureInit";
    
    //execute the function, passing it the $options array with all available options
    if(function_exists($feature_fn)) {
      $output = $feature_fn($options);
    } else {
      //you haven't created the correct function yet, so bail out
      return false;
    }
    
    return $output;
}