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class method
Date.new
(?::Integer year, ?::Integer month, ?::Integer mday, ?::Integer start) -> ::Date
Date.new(year = -4712, month = 1, mday = 1, start = Date::ITALY) → date
ext/date/date_core.c
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static VALUE
date_initialize(int argc, VALUE *argv, VALUE self)
{
VALUE vy, vm, vd, vsg, y, fr, fr2, ret;
int m, d;
double sg;
struct SimpleDateData *dat = rb_check_typeddata(self, &d_lite_type);
if (!simple_dat_p(dat)) {
rb_raise(rb_eTypeError, "Date expected");
}
rb_scan_args(argc, argv, "04", &vy, &vm, &vd, &vsg);
y = INT2FIX(-4712);
m = 1;
d = 1;
fr2 = INT2FIX(0);
sg = DEFAULT_SG;
switch (argc) {
case 4:
val2sg(vsg, sg);
case 3:
check_numeric(vd, "day");
num2int_with_frac(d, positive_inf);
case 2:
check_numeric(vm, "month");
m = NUM2INT(vm);
case 1:
check_numeric(vy, "year");
y = vy;
}
if (guess_style(y, sg) < 0) {
VALUE nth;
int ry, rm, rd;
if (!valid_gregorian_p(y, m, d,
&nth, &ry,
&rm, &rd))
rb_raise(eDateError, "invalid date");
set_to_simple(self, dat, nth, 0, sg, ry, rm, rd, HAVE_CIVIL);
}
else {
VALUE nth;
int ry, rm, rd, rjd, ns;
if (!valid_civil_p(y, m, d, sg,
&nth, &ry,
&rm, &rd, &rjd,
&ns))
rb_raise(eDateError, "invalid date");
set_to_simple(self, dat, nth, rjd, sg, ry, rm, rd, HAVE_JD | HAVE_CIVIL);
}
ret = self;
add_frac();
return ret;
}
Returns a new Date object constructed from the given arguments:
Example
Date.new(2022).to_s # => "2022-01-01" Date.new(2022, 2).to_s # => "2022-02-01" Date.new(2022, 2, 4).to_s # => "2022-02-04"
Argument month should be in range (1..12) or range (-12..-1); when the argument is negative, counts backward from the end of the year:
Example
Date.new(2022, -11, 4).to_s # => "2022-02-04"
Argument mday should be in range (1..n) or range (-n..-1) where n is the number of days in the month; when the argument is negative, counts backward from the end of the month.
See argument start.
Related: Date.jd.