Question

I am new to rails , currently i am working on code statistics for php,javascript/coffeescript repositories using ruby where i have a requirement to get no of coded lines and comment lines(single line and multi line comments) of php and javascript and coffeescript files using regular expressions . can any one help on this , thanks in advance

Answer 1

Here it is my man:

f = File.open("test.php")

loc = 0
comments = 0
while line = f.gets
  if commented ||= line.match(/^\/\*/)
    commented = nil if line.match(/\*\/$/)
    comments += 1
  elsif line.match(/^\s*\/\//)
    comments += 1
  else
    loc +=1 unless line.match(/^\s*\n/)
  end
end

puts loc
puts comments

This works for:

//line comments
/* inline block comments */
/* multi
line
comments */

How it works:

• You open the file
• Initialize the counters in 0
• Go trough each line with gets and assign it to the line variable
• If the line matches the beggining of a block comment set the commented variable
• Add 1 to comments variable
• If commented is set, search for the end of comment and set commented to nil if found
• Else if comment block not opened and “//” is found add 1 to comments
• Else add 1 to loc unless it’s an “empty” line