Question

I currently use soft tabs (i.e. spaces) for indenting my Ruby code, if I were to use hard tabs would it increase the performance when the code is interpreted? I assume it’s faster to read one tab character than parse 4 space characters (however negligible).

Answer 1

Do you have an idea of all the phases involved in interpreting from source? Only the very first one, lexical analysis, has to deal with whitespace, and in the case of whitespace, “deal with” means “ignore it”. This phase only takes a tiny fraction of the total time, it’s generally done using regular expression and pretty much has linear complexity. Constrast that with parsing, which can take ages in comparision. And interpreting is only somewhat viable because those two phases (plus a third, bytecode generation, in implementations that use bytecode) takes much less than the actual execution for nontrivial programs.

Don’t worry about this. There is no difference anyone would ever notice. Honestly, I’d be surprised if you could measure a difference using time and a small program that does close to no actual work.