Question

I am writing a PHP program which reads file with file_get_contents then attempts to count effective lines in that source file. It must not count empty lines or lines containing comments only. Sample file:

<?php

/**
  * blah blah
  */
class Test {
     // testfunc
     function testfunc(){


         return;
     }
}

The number of lines in such a file should be 5. Here is what I’ve got so far:

    $f=file_get_contents($this->file);
    $f=preg_replace('|/\*.*?\*/|s','',$f);
    $f=preg_replace('/^\s*$/','',$f);  // <-- does not work
    $f=preg_replace("/\n\n*/s","\n",$f);
    $count=count(explode("\n",$f));

But for some reason it does not eliminate white-spaces. Is there a better way to get this done?

---

The following code does the job, since I don’t care much about the spaces, but I still wonder, why my original line labeled “does not work” is not removing spaces from empty lines. Is there some extra character at the end? File format is unix.

    $f=preg_replace('/ */','',$f);   // removes all spaces properly.

Answer 1

Change /^[\s\t]*$/ to be /^\s*$/ms and that should fix it.
The \s class includes tabs, so no need to add \t. The s makes it match newline characters and the m option makes ^ and $ work when data contains multiple lines (matches line breaks).

Also, it might be better to change /\n\n/s to be /[\r\n]{2,}/.