End of Life Ruby 3.1 has reached end of life and gets no more fixes. Switch to Ruby 4.0 →

class method

Date.valid_civil?

Date.valid_civil?(year, month, mday[, start=Date::ITALY]) → bool

Date.valid_date?(year, month, mday[, start=Date::ITALY]) → bool

static VALUE
date_s_valid_civil_p(int argc, VALUE *argv, VALUE klass)
{
    VALUE vy, vm, vd, vsg;
    VALUE argv2[4];

    rb_scan_args(argc, argv, "31", &vy, &vm, &vd, &vsg);

    RETURN_FALSE_UNLESS_NUMERIC(vy);
    RETURN_FALSE_UNLESS_NUMERIC(vm);
    RETURN_FALSE_UNLESS_NUMERIC(vd);
    argv2[0] = vy;
    argv2[1] = vm;
    argv2[2] = vd;
    if (argc < 4)
        argv2[3] = INT2FIX(DEFAULT_SG);
    else
        argv2[3] = vsg;

    if (NIL_P(valid_civil_sub(4, argv2, klass, 0)))
        return Qfalse;
    return Qtrue;
}

Returns true if the given calendar date is valid, and false if not. Valid in this context is whether the arguments passed to this method would be accepted by ::new.

Example

Date.valid_date?(2001,2,3)        #=> true
Date.valid_date?(2001,2,29)       #=> false
Date.valid_date?(2001,2,-1)       #=> true