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  1. <?php
  2. $string = '//replace me please
  3. dont touch http://www.google.com
  4. or //this one
  5.   //but this one do as well';
  6. $regex = '/^\h*\/\/(.*)$/m';
  7. echo preg_replace($regex, '/*$1*/', $string);
Success #stdin #stdout 0.03s 52480KB
comments (?)
stdin 
Standard input is empty
stdout 
/*replace me please*/
dont touch http://www.google.com
or //this one
/*but this one do as well*/
https://ideone.com/j7Xj4L
language:
PHP (php 7.3.5)
created:
10 years ago
visibility:
public

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