Equivalent in ruby of PHP's .= operator?

I'm looking to concatenate a string in a loop, like this, but in Ruby:

$fizz = file_get_contents($_SERVER['argv'][1]);
$output = "";
for($i=1;$i<=$fizz;$i++) {
    if($i % 3 == 0 && !($i % 5 ==0)) {
        $output .= "fizz\n";
    }
    else if($i % 5 == 0 && !($i % 3 ==开发者_开发问答0)) {
        $output .= "buzz\n";
    }
    else if($i % 3 == 0 && $i % 5 == 0) {
        $output .= "FizzBuzz\n";
    }
}
print $output;
?>

I'm also interested in finding out what the name of the ".=" type operator is called so I can Google search these things better.

Using Ruby 1.8.6.

You are looking for Ruby's String#<<.

So, your code might look like this:

variable << "fizz\n"

Here is the documentation for the << (aka concat) method.

I don't know Ruby, but a quick search for Ruby String Concatenation (the operator is not a really an operator (PHP is just.. special, and not necessarily the good kind), it's called string concatenation) gives the following:

myString = "Welcome " + "to " + "Ruby!" - Standard concatenation across most languages.

myString = "Welcome " "to " "Ruby!" - Omits + sign

myString = "Welcome " << "to " << "Ruby!" - c++ cout style.

The content of myString will all be "Welcome to Ruby".

Maybe you could even do += (equivilant to .=)

Watch out for freeze strings.. apparently.

More info: http://www.techotopia.com/index.php/Ruby_String_Concatenation_and_Comparison

Is there a real reason you need to solve it this way? This can be expressed in Ruby like so:

(1..100).each do |number|
  if number % 15 == 0
    puts "#{number} FizzBuzz"
  elsif number % 5 == 0
    puts "#{number} Buzz"
  elsif number % 3 == 0
    puts "#{number} Fizz"
  end
end

Using (1..100) is a range which mixes in Enumerable so we can iterate over the items.

If the fizzbuzz problem allows for printing all numbers (as some interpretations do), then here's a variant of Caley Woods example above, showcasing the way case statements return values

(1..100).each do |number|
  puts number.to_s << case 0
   when number % 15
     " FizzBuzz"
   when number % 5
     " Buzz"
   when number % 3
     " Fizz"
   else
     ""
   end
end