Angus asked me today to code him a method in Ruby to work out if a date is a leap year. He gave his example:
[code=”Angus’s Example”] if not (year % 4) and ((year % 100) or not ((year % 100) or (year % 400))) [/code]
| *tut tuts Angus, use ! instead of not, && instead of and, and | instead of or!* |
Ruby has this built in method called [term]leap?[/term] and its source looks like this:
[code=”Ruby’s Source”] def leap? self.class.jd_to_civil(self.class.civil_to_jd(year, 3, 1, ns?) - 1, ns?)[-1] == 29 end [/code]
Now I’m sure there’s a reason they’re doing all that, but I have a shorter way:
[code=”My Code”] class Date def leap? yday != 60 end end [/code]
[term]yday[/term] returns 60 on all years that are not leap years, so why not just check that value?