在rebol中有一个对象构造函数

实际上，通过再次阅读Rebol Core文档（我只是遵循了很好的旧建议：“阅读法语手册”），还有另一种实现构造函数的方法，非常简单：

http://www.rebol.com/docs/core-fr/fr-rebolcore-10.html#section-8

当然在《英语手册》中也有：

http://www.rebol.com/docs/core23/rebolcore-10.html#section-7

=>

使用self变量的另一个示例是克隆自身的函数：

person: make object! [
    name: days-old: none
    new: func [name' birthday] [
        make self [
            name: name'
            days-old: now/date - birthday
        ]
    ]
]

lulu: person/new "Lulu Ulu" 17-May-1980

print lulu/days-old
7366

我发现这很方便，这样，构造函数就位于对象内。这一事实使对象更加自给自足。

我刚刚成功地将其应用于某些地质学方面，并且效果很好：

>> source orientation
orientation: make object! [
    matrix: []
    north_reference: "Nm"
    plane_quadrant_dip: ""
    new: func [{Constructor, builds an orientation object! based on a measurement, as given by GeolPDA device, a rotation matrix represented by a suite of 9 values} m][
        make self [
            foreach [a b c] m [append/only matrix to-block reduce [a b c]] 
            a: self/matrix/1/1 
            b: self/matrix/1/2 
            c: self/matrix/1/3 
            d: self/matrix/2/1 
            e: self/matrix/2/2 
            f: self/matrix/2/3 
            g: self/matrix/3/1 
            h: self/matrix/3/2 
            i: self/matrix/3/3 
            plane_normal_vector: reduce [matrix/1/3 
                matrix/2/3 
                matrix/3/3
            ] 
            axis_vector: reduce [self/matrix/1/2 
                self/matrix/2/2 
                self/matrix/3/2
            ] 
            plane_downdip_azimuth: azimuth_vector plane_normal_vector 
            plane_direction: plane_downdip_azimuth - 90 
            if (plane_direction < 0) [plane_direction: plane_direction - 180] 
            plane_dip: arccosine (plane_normal_vector/3) 
            case [
                ((plane_downdip_azimuth > 315) or (plane_downdip_azimuth <= 45)) [plane_quadrant_dip: "N"] 
                ((plane_downdip_azimuth > 45) and (plane_downdip_azimuth <= 135)) [plane_quadrant_dip: "E"] 
                ((plane_downdip_azimuth > 135) and (plane_downdip_azimuth <= 225)) [plane_quadrant_dip: "S"] 
                ((plane_downdip_azimuth > 225) and (plane_downdip_azimuth <= 315)) [plane_quadrant_dip: "W"]
            ] 
            line_azimuth: azimuth_vector axis_vector 
            line_plunge: 90 - (arccosine (axis_vector/3))
        ]
    ]
    repr: func [][
        print rejoin ["Matrix: " tab self/matrix 
            newline 
            "Plane: " tab 
            north_reference to-string to-integer self/plane_direction "/" to-string to-integer self/plane_dip "/" self/plane_quadrant_dip 
            newline 
            "Line: " tab 
            rejoin [north_reference to-string to-integer self/line_azimuth "/" to-string to-integer self/line_plunge]
        ]
    ]
    trace_te: func [diagram [object!]][
        len_queue_t: 0.3 
        tmp: reduce [
            plane_normal_vector/1 / (square-root (((plane_normal_vector/1 ** 2) + (plane_normal_vector/2 ** 2)))) 
            plane_normal_vector/2 / (square-root (((plane_normal_vector/1 ** 2) + (plane_normal_vector/2 ** 2))))
        ] 
        O: [0 0] 
        A: reduce [- tmp/2 
            tmp/1
        ] 
        B: reduce [tmp/2 0 - tmp/1] 
        C: reduce [tmp/1 * len_queue_t 
            tmp/2 * len_queue_t
        ] 
        L: reduce [- axis_vector/1 0 - axis_vector/2] 
        append diagram/plot [pen black] 
        diagram/trace_line A B 
        diagram/trace_line O C 
        diagram/trace_line O L
    ]
]
>> o: orientation/new [0.375471 -0.866153 -0.32985 0.669867 0.499563 -0.549286 0.640547 -0.0147148 0.767778]
>> o/repr
Matrix:     0.375471 -0.866153 -0.32985 0.669867 0.499563 -0.549286 0.640547 -0.0147148 0.767778
Plane:  Nm120/39/S
Line:   Nm299/0

这种方式的另一个优点是，“ new”方法定义的变量直接属于对象“ instance”（我遇到了麻烦，其他方法不得不提到self /有时必须初始化变量或不初始化变量）。