Most convenient way to write a loop with fixed length and no need for the index?

[Martin Tschierschke via Digitalmars-d-learn]

What do I have to do, to make this work?

iota(number).each!...command_x(a...);command_y(b...);command_z(c..))
                  ^^^^^?
how to write the lambda?

Similar to the ruby (1..number).each{ commands...}

Don't want to write the following, because the index i is not 
used inside the loop
and this should be clear when reading it:

   for (i=0;i<number;i++){commands...}

or

   foreach(i;iota(number)){commands...}

Or is there something like number.times!{....} possible?