It's the same on 0.4, and Strings are getting a big overhaul on 0.5. Here are the results for 0.4: $ julia -e 'f(a, b) = @sprintf("this is a %s %15.1f", a

It's the same on 0.4, and Strings are getting a big overhaul on 0.5. Here are the results for 0.4: $ julia -e 'f(a, b) = @sprintf("this is a %s %15.1f", a, b); code_native(f, (AbstractString, Float64))' | wc -l WARNING: Returned code may not match what actually runs. 628 $ julia -e 'f(a, b) = @sprintf("this is a %s %15.1f", a, b); code_native(f, (ASCIIString, Float64))' | wc -l 194 $ julia -e 'f(a, b) = @sprintf("this is a %s %15.1f", a, b); code_native(f, (UTF8String, Float64))' | wc -l 194