If you have pickaxe2, look at page 339. Most languages that have expressions like this know the typical order of operation for things that come from the world of math. Be careful with this since - and * can be redefined based on the classes they're operating on: >> a = %w(h t h h h t t t h h t h) => ["h", "t", "h", "h", "h", "t", "t", "t", "h", "h", "t", "h"] >> b = [ "h" ] => ["h"] >> c = 7 => 7 >> a = a - b*c => ["t", "t", "t", "t", "t"] -Rob Rob Biedenharn http://agileconsultingllc.com Rob / AgileConsultingLLC.com On Jun 30, 2006, at 12:07 PM, Dark Ambient wrote: > Just checking > > if I have > > a = a - b*c > > b*c gets calculated first then that result is subtracted from a ? > In other words, parantheses, in Ruby, is not necessary to make that > calculation ? > > TIA > Stuart >