What does the ' %s ' mean ?

rubyonrails-talk
1

Hi there,

can anyone explain to me how I have to understand the:

  %s

in the following code line:

  yield :error, "There was a problem resending your activation code, please try again or %s.", "resend_activation_path"

Whant does it stand for, what does it mean, what does it do?

Thanks! Tom

2

Tom Ha wrote:

  yield :error, "There was a problem resending your activation code, please try again or %s.", "resend_activation_path"

Whant does it stand for, what does it mean, what does it do?

Google for "printf", alone.

3

I’m not familiar with that particular bit of code, but I think this relates to the “%” method for String classes in ruby. See http://www.ruby-doc.org/core/classes/String.html#M000785 .

This is ruby’s way of doing format control letters and modifiers. If you’ve programmed in C etc or something like awk, you often use these in print statements (eg printf) to format strings and numbers etc.

Whenever I have to look these up I check out the gawk reference - here’s one online: http://www.gnu.org/software/gawk/manual/gawk.html#Control-Letters

Simple example in ruby:

“foo%s” % “bar” => “foobar”

“foo%05d” % 1 => “foo00001”