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class method
Date.julian_leap?
Date.julian_leap?(year) → bool
ext/date/date_core.c
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static VALUE
date_s_julian_leap_p(VALUE klass, VALUE y)
{
VALUE nth;
int ry;
check_numeric(y, "year");
decode_year(y, +1, &nth, &ry);
return f_boolcast(c_julian_leap_p(ry));
}
Returns true if the given year is a leap year of the proleptic Julian calendar.
Example
Date.julian_leap?(1900) #=> true Date.julian_leap?(1901) #=> false