SysML v2 — Ran Wei

模块 8：变体与配置

如何定义变体点、声明可选变体并配置产品线 — 让一个模型就能刻画整个系统配置族。

★

KerML → SysML：可变性概念

SysML v2 的可变性建立在 KerML 的使用变体（usage variation）与变体成员关系（variant membership）机制之上。variation 使用声明一个可变点 — 该特征必须恰好绑定到其允许的备选项之一。变体点内的每个 variant 都是一个独立的成员选项。在 KerML 层面，这些都通过使用上的特征成员关系与子集关系来建模。

表 0 — 模块 8 的 SysML v2（L2）可变性概念到 KerML（L1）起源的映射
SysML v2 概念（L2）	底层 KerML 构造（L1）	SysML 增加了什么
`variation`（作用于使用）	`isVariation = true` 的 Usage	把某个特征标记为变体点；在任何完整配置中都必须解析为恰好一个变体
`variant`	`VariantMembership`（一种 `OwningMembership`）	在变体点内声明一个具名备选项；每个变体都是该变体使用的子集
`variation part def`	`isVariation = true` 的 `PartDefinition`	其使用天然即为变体点的定义 — 每次使用都必须被解析
`variant`（位于变体定义内）	拥有某个使用的 `VariantMembership`	在变体定义中充当一个选项的使用
配置绑定	把变体解析到某个具体变体的 `BindingConnector`	固定该选择；产出一个完整解析的产品实例
`filter` 表达式	`FilterExpression`（作用于元数据的布尔表达式）	依据元数据条件从包或命名空间中挑选元素
产品线包	混合了变体与非变体内容的 `Package`	把共享平台元素与产品族的变体点组织在一起

说明

在 KerML 中，isVariation 是任意 Usage 上的布尔属性。当它为 true 时，该使用即成为变体点，其带 VariantMembership 的自有成员就是允许的选项。SysML v2 用 variation 与 variant 关键字为这套机制提供了语法糖。

变体点

KerML 起源：variation → isVariation = true 的 Usage

变体点是模型中代表一次选择的特征 — 不同配置正是在这里产生差异。在 SysML v2 中，给使用加上 variation 前缀即可声明变体点。变体使用本身并不是具体元素，而是一个占位符：在任何完整配置中，它都必须被解析为某一个变体。

类比

可以想象一份餐厅菜单。菜单上的「主菜」这一栏就是变体点 — 每位客人必须且只能选一项。具体的菜品（牛排、鱼、意面）则是变体。菜单定义结构，而每位客人点的那一单就是一个配置。

零件使用上的变体

最常见的变体形式作用在零件定义内的零件使用上。variation 关键字声明该特征是一个可变点，variant 成员则声明允许的备选项：


1 part def Vehicle {
2     part engine : Engine;
3 
4     // Variation point: transmission type
5     variation part transmission : Transmission {
6         variant part manual    : ManualTransmission;
7         variant part automatic : AutomaticTransmission;
8         variant part cvt       : CVTTransmission;
9     }
10 }

在这个模型中，每个 Vehicle 实例都必须恰好有一套变速器 — 手动、自动或 CVT 三者取一。变体点不是可选项，它强制要求作出选择。

属性使用上的变体

变体点并不限于零件。你可以把它用在属性、端口或任何其他种类的使用上：


1 part def Display {
2     // Variation point: screen resolution
3     variation attribute resolution : ScreenResolution {
4         variant attribute hd   : HD;    // 1280x720
5         variant attribute fhd  : FHD;   // 1920x1080
6         variant attribute uhd  : UHD;   // 3840x2160
7     }
8 }

常见误区

变体点必须至少包含一个 variant 成员。声明一个没有任何变体的 variation 使用属于语义错误 — 因为根本无从选择。工具应把它标记为不完整。

变体定义

KerML 起源：variant → VariantMembership（一种 OwningMembership）

变体是变体点内的一个具体备选项。每个变体都是完整规定的元素 — 它带有自己的特征、约束和子结构。当某个配置选中一个变体时，在解析后的模型中，该变体的完整定义就取代了原来的变体点。

内联变体定义

变体可以直接内联定义在变体点里，并带上各自特有的特征：


1 part def Powertrain {
2     variation part motorType : Motor {
3         variant part ice : ICEMotor {
4             attribute displacement : ISQ::VolumeValue;
5             attribute cylinders    : ScalarValues::Integer;
6         }
7         variant part electric : ElectricMotor {
8             attribute peakPower   : ISQ::PowerValue;
9             attribute batteryCapacity : ISQ::EnergyValue;
10         }
11         variant part hybrid : HybridMotor {
12             attribute displacement : ISQ::VolumeValue;
13             attribute peakPower   : ISQ::PowerValue;
14         }
15     }
16 }

引用外部的变体定义

变体也可以引用单独定义的零件定义。当同一个变体出现在模型中多个变体点里时，这种写法很有用：


1 part def ManualTransmission :> Transmission {
2     attribute gearCount : ScalarValues::Integer;
3 }
4 
5 part def AutomaticTransmission :> Transmission {
6     attribute modes : DriveMode[1..*];
7 }
8 
9 part def Vehicle {
10     // Variants reference externally defined part defs
11     variation part transmission : Transmission {
12         variant part manual    : ManualTransmission;
13         variant part automatic : AutomaticTransmission;
14     }
15 }

变体定义（定义级）

你也可以用 variation part def 把整个定义标记为变体。这意味着该定义本身是抽象的 — 它不能被直接实例化，而必须解析为它的某个变体成员：


1 variation part def DriveMode {
2     variant eco   : EcoMode;
3     variant sport : SportMode;
4     variant normal: NormalMode;
5 }

说明

要区分作用在使用上的 variation 与作用在定义上的 variation。变体使用是一个必须在上下文中被解析的具体特征；变体定义则声明类型本身就是一个变体 — 该定义的每一次使用都继承变体点语义。

配置管理

KerML 起源：配置绑定 → 把变体解析到某个具体变体的 BindingConnector

配置是对模型中全部变体点的一次具体解析。它为每个变体点恰好选定一个变体，从而产出一个完整规定的产品实例。在 SysML v2 中，配置通过特化产品定义、并把每个变体使用绑定到所选变体来建模。

通过特化创建配置

标准做法是新建一个零件定义或使用，特化那个可变的产品，并绑定每一个变体点：


1 // Base product with variation points
2 part def Vehicle {
3     part engine : Engine;
4     variation part transmission : Transmission {
5         variant part manual    : ManualTransmission;
6         variant part automatic : AutomaticTransmission;
7     }
8     variation part infotainment : Infotainment {
9         variant part basic   : BasicInfotainment;
10         variant part premium : PremiumInfotainment;
11     }
12 }
13 
14 // Configuration: Sport Edition
15 part def SportEdition :> Vehicle {
16     // Resolve transmission to manual
17     part transmission redefines Vehicle::transmission = transmission::manual;
18     // Resolve infotainment to premium
19     part infotainment redefines Vehicle::infotainment = infotainment::premium;
20 }
21 
22 // Configuration: Economy Edition
23 part def EconomyEdition :> Vehicle {
24     part transmission redefines Vehicle::transmission = transmission::automatic;
25     part infotainment redefines Vehicle::infotainment = infotainment::basic;
26 }

部分配置

并非每个配置都必须解析全部变体点。部分配置只解析其中一部分，其余保持开放。这在为产品档次或区域变体建模时很有用 — 某些选择已经固定，另一些仍需灵活：


1 // Partial configuration: European variant (fixes transmission, leaves infotainment open)
2 part def EuropeanVehicle :> Vehicle {
3     part transmission redefines Vehicle::transmission = transmission::manual;
4     // infotainment variation point remains unresolved
5 }
6 
7 // Full configuration: European Sport (resolves remaining variation)
8 part def EuropeanSport :> EuropeanVehicle {
9     part infotainment redefines Vehicle::infotainment = infotainment::premium;
10 }

提示

可以用部分配置搭建分层的配置体系：从基础产品出发，先做区域级或档次级的部分配置，再在叶节点做完全解析的配置。这与汽车主机厂在实践中管理产品线的方式一致。

过滤与选择

KerML 起源：filter → FilterExpression（作用于元数据的布尔表达式）

过滤表达式提供一种查询机制，可依据元数据条件从命名空间中挑选元素。与直接的变体绑定不同，过滤器可以跨包工作，并能同时选中多个元素。它与元数据注解配合使用时尤其强大。

基本过滤语法

filter 表达式是施加于包内元素的布尔谓词。只有满足该谓词的元素才会出现在过滤后的视图中：


1 // Metadata for tagging elements
2 metadata def Region {
3     attribute name : ScalarValues::String;
4 }
5 
6 metadata def Tier {
7     attribute level : ScalarValues::String;
8 }
9 
10 package AllFeatures {
11     part heatedSeats : HeatedSeats {
12         @Region { name = "EU"; }
13         @Tier { level = "premium"; }
14     }
15     part airCon : AirConditioning {
16         @Region { name = "ALL"; }
17         @Tier { level = "basic"; }
18     }
19     part sunroof : PanoramicSunroof {
20         @Region { name = "US"; }
21         @Tier { level = "premium"; }
22     }
23 }

应用过滤表达式

过滤表达式依据元数据从包中挑选元素。被过滤的包充当一个视图 — 它并不复制元素，而是给出一个受限的子集：


1 // Select only premium-tier features
2 package PremiumFeatures {
3     import AllFeatures::**;
4     filter @Tier and Tier::level == "premium";
5 }
6 
7 // Select only EU-region features
8 package EUFeatures {
9     import AllFeatures::**;
10     filter @Region and (Region::name == "EU" or Region::name == "ALL");
11 }

说明

过滤表达式作用于元数据注解。它们不会修改底层模型 — 只是产出一个仅含匹配元素的模型视图。这在概念上类似数据库查询：数据本身没变，只是结果集被收窄了。

把过滤器与变体结合使用

过滤器与变体点是互补机制。变体点定义的是强制选择（必须选一个）；过滤器定义的是可选纳入（满足条件才纳入）。设计良好的产品线两者兼用：

变体点用于结构性备选（发动机类型、车身形式）
过滤器用于功能包（舒适选装、区域合规功能）

常见误区

不要用过滤器替代变体点。过滤器是从既有集合中挑选，变体点则声明一次强制选择。如果每个产品都必须在若干备选中恰好取一个，请用 variation/variant；如果某项功能是依据元数据有条件地纳入，才用 filter。

产品线建模

KerML 起源：产品线 → 混合了变体与非变体内容的 Package

产品线是一族共享同一平台、但在具体功能上有所差异的产品。SysML v2 通过共享定义（平台）、变体点（可配置的部分）与配置（已解析的产品）三者的组合来支持产品线建模。

平台 + 变体策略

推荐的模式把模型分为三层：

平台包 — 共享定义、不变结构与公共约束
可变性包 — 变体点与变体定义
配置包 — 绑定了全部变体点的完整产品


1 package Platform {
2     // Shared across all products
3     part def Chassis { attribute wheelbase : ISQ::LengthValue; }
4     part def BrakeSystem { part frontBrakes : DiscBrake; part rearBrakes : DiscBrake; }
5     part def SteeringSystem { attribute ratio : ScalarValues::Real; }
6 }
7 
8 package Variability {
9     private import Platform::*;
10 
11     part def ProductVehicle {
12         part chassis  : Chassis;       // from platform (invariant)
13         part brakes   : BrakeSystem;   // from platform (invariant)
14         part steering : SteeringSystem; // from platform (invariant)
15 
16         // Variable aspects
17         variation part body : BodyStyle {
18             variant part sedan : SedanBody;
19             variant part suv   : SUVBody;
20             variant part truck : TruckBody;
21         }
22         variation part powertrain : Powertrain {
23             variant part petrol   : PetrolPowertrain;
24             variant part diesel   : DieselPowertrain;
25             variant part electric : ElectricPowertrain;
26         }
27     }
28 }
29 
30 package Configurations {
31     private import Variability::*;
32 
33     part def SedanPetrol :> ProductVehicle {
34         part body redefines ProductVehicle::body = body::sedan;
35         part powertrain redefines ProductVehicle::powertrain = powertrain::petrol;
36     }
37 
38     part def SUVElectric :> ProductVehicle {
39         part body redefines ProductVehicle::body = body::suv;
40         part powertrain redefines ProductVehicle::powertrain = powertrain::electric;
41     }
42 }

约束在变体间的传播

定义在平台或基础产品上的约束适用于全部配置；变体特有的约束则可以加在变体层级上：


1 part def ProductVehicle {
2     // Platform constraint: applies to ALL configurations
3     assert constraint maxWeight {
4         chassis.totalMass <= 2500[kg]
5     }
6 
7     variation part body : BodyStyle {
8         variant part truck : TruckBody {
9             // Variant-specific constraint: only applies when truck is selected
10             assert constraint towingCapacity {
11                 payloadCapacity >= 1000[kg]
12             }
13         }
14     }
15 }

提示

三层模式（平台、可变性、配置）具有良好的可扩展性：平台包可由平台工程团队维护，可变性包由产品管理负责，配置包则由各产品团队负责。每一层从下一层导入内容。

完整示例

下面的模型整合了本模块的全部概念：一条车辆产品线，包含轿车、SUV 与皮卡三种变体，共享同一平台，各自具备动力总成与功能级的可变性，并配有元数据驱动的过滤和完整解析的配置。


1 package VehicleProductLine {
2     private import ISQ::*;
3     private import SI::*;
4     private import ScalarValues::*;
5 
6     // ── Metadata for filtering ──────────────────────────────
7     metadata def MarketRegion {
8         attribute region : String;
9     }
10     metadata def FeatureTier {
11         attribute tier : String;
12     }
13 
14     // ── Shared platform ─────────────────────────────────────
15     part def Chassis {
16         attribute wheelbase : LengthValue;
17         attribute curbWeight : MassValue;
18     }
19     part def BrakeSystem {
20         part frontBrakes : DiscBrake;
21         part rearBrakes  : DiscBrake;
22         part abs : ABSController;
23     }
24     part def SteeringSystem {
25         attribute steeringRatio : Real;
26     }
27 
28     // ── Body style variants ──────────────────────────────────
29     part def BodyStyle;
30     part def SedanBody :> BodyStyle {
31         attribute doorCount   : Integer = 4;
32         attribute trunkVolume : VolumeValue;
33     }
34     part def SUVBody :> BodyStyle {
35         attribute doorCount     : Integer = 5;
36         attribute groundClearance : LengthValue;
37         attribute roofRails     : Boolean = true;
38     }
39     part def TruckBody :> BodyStyle {
40         attribute doorCount      : Integer = 4;
41         attribute bedLength      : LengthValue;
42         attribute payloadCapacity : MassValue;
43     }
44 
45     // ── Powertrain variants ──────────────────────────────────
46     part def Powertrain;
47     part def PetrolPowertrain :> Powertrain {
48         attribute displacement : VolumeValue;
49         attribute cylinders    : Integer;
50         attribute maxPower     : PowerValue;
51     }
52     part def DieselPowertrain :> Powertrain {
53         attribute displacement : VolumeValue;
54         attribute maxTorque    : ForceValue;
55     }
56     part def ElectricPowertrain :> Powertrain {
57         attribute batteryCapacity : EnergyValue;
58         attribute range           : LengthValue;
59         attribute chargePower     : PowerValue;
60     }
61 
62     // ── Optional feature packages (metadata-tagged) ─────────
63     package FeatureCatalog {
64         part heatedSeats : HeatedSeats {
65             @MarketRegion { region = "ALL"; }
66             @FeatureTier { tier = "premium"; }
67         }
68         part adaptiveCruise : AdaptiveCruiseControl {
69             @MarketRegion { region = "ALL"; }
70             @FeatureTier { tier = "premium"; }
71         }
72         part towHitch : TowHitch {
73             @MarketRegion { region = "US"; }
74             @FeatureTier { tier = "basic"; }
75         }
76         part headlightWashers : HeadlightWashers {
77             @MarketRegion { region = "EU"; }
78             @FeatureTier { tier = "basic"; }
79         }
80     }
81 
82     // ── Base product with variation points ───────────────────
83     part def Vehicle {
84         // Platform (invariant across all configurations)
85         part chassis  : Chassis;
86         part brakes   : BrakeSystem;
87         part steering : SteeringSystem;
88 
89         // Variation point 1: body style
90         variation part body : BodyStyle {
91             variant part sedan : SedanBody;
92             variant part suv   : SUVBody;
93             variant part truck : TruckBody;
94         }
95 
96         // Variation point 2: powertrain
97         variation part powertrain : Powertrain {
98             variant part petrol   : PetrolPowertrain;
99             variant part diesel   : DieselPowertrain;
100             variant part electric : ElectricPowertrain;
101         }
102 
103         // Platform constraint: all variants must satisfy
104         assert constraint maxGrossWeight {
105             chassis.curbWeight <= 3000[kg]
106         }
107     }
108 
109     // ── Filtered feature views ───────────────────────────────
110     package PremiumFeatures {
111         import FeatureCatalog::**;
112         filter @FeatureTier and FeatureTier::tier == "premium";
113     }
114     package USFeatures {
115         import FeatureCatalog::**;
116         filter @MarketRegion and (MarketRegion::region == "US"
117                                 or MarketRegion::region == "ALL");
118     }
119     package EUFeatures {
120         import FeatureCatalog::**;
121         filter @MarketRegion and (MarketRegion::region == "EU"
122                                 or MarketRegion::region == "ALL");
123     }
124 
125     // ── Fully resolved configurations ────────────────────────
126     part def SedanPetrolUS :> Vehicle {
127         part body redefines Vehicle::body = body::sedan;
128         part powertrain redefines Vehicle::powertrain = powertrain::petrol;
129         // Include US-market features from the filtered view
130     }
131 
132     part def SUVElectricEU :> Vehicle {
133         part body redefines Vehicle::body = body::suv;
134         part powertrain redefines Vehicle::powertrain = powertrain::electric;
135         // Include EU-market features from the filtered view
136     }
137 
138     part def TruckDieselUS :> Vehicle {
139         part body redefines Vehicle::body = body::truck;
140         part powertrain redefines Vehicle::powertrain = powertrain::diesel;
141 
142         // Truck-specific constraint override
143         assert constraint towRating {
144             body.payloadCapacity >= 1500[kg]
145         }
146     }
147 }

该模型演示了：共享平台（底盘、制动、转向）、两个各含三个变体的变体点（车身形式、动力总成）、带市场区域与档次过滤表达式的元数据标记选装功能、适用于全部配置的平台级约束、变体特有约束（皮卡拖挂能力），以及面向不同细分市场的三个完整解析配置。

模块总结

表 — 模块 8 的概念及其 KerML 起源
SysML v2 概念	KerML 起源	关键规则
`variation`（作用于使用）	`isVariation = true` 的 Usage	把某个特征标记为变体点；必须解析为恰好一个变体
`variant`	`VariantMembership`	在变体点内声明一个允许的备选项
`variation part def`	`isVariation = true` 的 `PartDefinition`	定义本身即是变体；其每次使用都继承变体语义
配置绑定	`BindingConnector`	通过 `redefines` 把变体使用解析到某个具体变体
部分配置	仍有部分变体未解析的特化	固定一部分选择，其余留待进一步特化
`filter` 表达式	`FilterExpression`	依据元数据条件从命名空间中挑选元素；产出一个视图
产品线包	内容混合的 Package	三层模式：平台 + 可变性 + 配置
元数据标记	元数据注解	为元素标注区域、档次等筛选条件，供过滤使用

下一模块

模块 9 — 验证与确认 — 如何定义验证用例、把它们绑定到需求、为验证方法建模，并把 V&V 融入系统工程生命周期。

1	part def Vehicle {
2	part engine : Engine;
3
4	// Variation point: transmission type
5	variation part transmission : Transmission {
6	variant part manual : ManualTransmission;
7	variant part automatic : AutomaticTransmission;
8	variant part cvt : CVTTransmission;
9	}
10	}

1	part def Display {
2	// Variation point: screen resolution
3	variation attribute resolution : ScreenResolution {
4	variant attribute hd : HD; // 1280x720
5	variant attribute fhd : FHD; // 1920x1080
6	variant attribute uhd : UHD; // 3840x2160
7	}
8	}

1	part def Powertrain {
2	variation part motorType : Motor {
3	variant part ice : ICEMotor {
4	attribute displacement : ISQ::VolumeValue;
5	attribute cylinders : ScalarValues::Integer;
6	}
7	variant part electric : ElectricMotor {
8	attribute peakPower : ISQ::PowerValue;
9	attribute batteryCapacity : ISQ::EnergyValue;
10	}
11	variant part hybrid : HybridMotor {
12	attribute displacement : ISQ::VolumeValue;
13	attribute peakPower : ISQ::PowerValue;
14	}
15	}
16	}

1	part def ManualTransmission :> Transmission {
2	attribute gearCount : ScalarValues::Integer;
3	}
4
5	part def AutomaticTransmission :> Transmission {
6	attribute modes : DriveMode[1..*];
7	}
8
9	part def Vehicle {
10	// Variants reference externally defined part defs
11	variation part transmission : Transmission {
12	variant part manual : ManualTransmission;
13	variant part automatic : AutomaticTransmission;
14	}
15	}

1	variation part def DriveMode {
2	variant eco : EcoMode;
3	variant sport : SportMode;
4	variant normal: NormalMode;
5	}

1	// Base product with variation points
2	part def Vehicle {
3	part engine : Engine;
4	variation part transmission : Transmission {
5	variant part manual : ManualTransmission;
6	variant part automatic : AutomaticTransmission;
7	}
8	variation part infotainment : Infotainment {
9	variant part basic : BasicInfotainment;
10	variant part premium : PremiumInfotainment;
11	}
12	}
13
14	// Configuration: Sport Edition
15	part def SportEdition :> Vehicle {
16	// Resolve transmission to manual
17	part transmission redefines Vehicle::transmission = transmission::manual;
18	// Resolve infotainment to premium
19	part infotainment redefines Vehicle::infotainment = infotainment::premium;
20	}
21
22	// Configuration: Economy Edition
23	part def EconomyEdition :> Vehicle {
24	part transmission redefines Vehicle::transmission = transmission::automatic;
25	part infotainment redefines Vehicle::infotainment = infotainment::basic;
26	}

1	// Partial configuration: European variant (fixes transmission, leaves infotainment open)
2	part def EuropeanVehicle :> Vehicle {
3	part transmission redefines Vehicle::transmission = transmission::manual;
4	// infotainment variation point remains unresolved
5	}
6
7	// Full configuration: European Sport (resolves remaining variation)
8	part def EuropeanSport :> EuropeanVehicle {
9	part infotainment redefines Vehicle::infotainment = infotainment::premium;
10	}

1	// Metadata for tagging elements
2	metadata def Region {
3	attribute name : ScalarValues::String;
4	}
5
6	metadata def Tier {
7	attribute level : ScalarValues::String;
8	}
9
10	package AllFeatures {
11	part heatedSeats : HeatedSeats {
12	@Region { name = "EU"; }
13	@Tier { level = "premium"; }
14	}
15	part airCon : AirConditioning {
16	@Region { name = "ALL"; }
17	@Tier { level = "basic"; }
18	}
19	part sunroof : PanoramicSunroof {
20	@Region { name = "US"; }
21	@Tier { level = "premium"; }
22	}
23	}

1	// Select only premium-tier features
2	package PremiumFeatures {
3	import AllFeatures::**;
4	filter @Tier and Tier::level == "premium";
5	}
6
7	// Select only EU-region features
8	package EUFeatures {
9	import AllFeatures::**;
10	filter @Region and (Region::name == "EU" or Region::name == "ALL");
11	}

1	package Platform {
2	// Shared across all products
3	part def Chassis { attribute wheelbase : ISQ::LengthValue; }
4	part def BrakeSystem { part frontBrakes : DiscBrake; part rearBrakes : DiscBrake; }
5	part def SteeringSystem { attribute ratio : ScalarValues::Real; }
6	}
7
8	package Variability {
9	private import Platform::*;
10
11	part def ProductVehicle {
12	part chassis : Chassis; // from platform (invariant)
13	part brakes : BrakeSystem; // from platform (invariant)
14	part steering : SteeringSystem; // from platform (invariant)
15
16	// Variable aspects
17	variation part body : BodyStyle {
18	variant part sedan : SedanBody;
19	variant part suv : SUVBody;
20	variant part truck : TruckBody;
21	}
22	variation part powertrain : Powertrain {
23	variant part petrol : PetrolPowertrain;
24	variant part diesel : DieselPowertrain;
25	variant part electric : ElectricPowertrain;
26	}
27	}
28	}
29
30	package Configurations {
31	private import Variability::*;
32
33	part def SedanPetrol :> ProductVehicle {
34	part body redefines ProductVehicle::body = body::sedan;
35	part powertrain redefines ProductVehicle::powertrain = powertrain::petrol;
36	}
37
38	part def SUVElectric :> ProductVehicle {
39	part body redefines ProductVehicle::body = body::suv;
40	part powertrain redefines ProductVehicle::powertrain = powertrain::electric;
41	}
42	}

1	part def ProductVehicle {
2	// Platform constraint: applies to ALL configurations
3	assert constraint maxWeight {
4	chassis.totalMass <= 2500[kg]
5	}
6
7	variation part body : BodyStyle {
8	variant part truck : TruckBody {
9	// Variant-specific constraint: only applies when truck is selected
10	assert constraint towingCapacity {
11	payloadCapacity >= 1000[kg]
12	}
13	}
14	}
15	}

1	package VehicleProductLine {
2	private import ISQ::*;
3	private import SI::*;
4	private import ScalarValues::*;
5
6	// ── Metadata for filtering ──────────────────────────────
7	metadata def MarketRegion {
8	attribute region : String;
9	}
10	metadata def FeatureTier {
11	attribute tier : String;
12	}
13
14	// ── Shared platform ─────────────────────────────────────
15	part def Chassis {
16	attribute wheelbase : LengthValue;
17	attribute curbWeight : MassValue;
18	}
19	part def BrakeSystem {
20	part frontBrakes : DiscBrake;
21	part rearBrakes : DiscBrake;
22	part abs : ABSController;
23	}
24	part def SteeringSystem {
25	attribute steeringRatio : Real;
26	}
27
28	// ── Body style variants ──────────────────────────────────
29	part def BodyStyle;
30	part def SedanBody :> BodyStyle {
31	attribute doorCount : Integer = 4;
32	attribute trunkVolume : VolumeValue;
33	}
34	part def SUVBody :> BodyStyle {
35	attribute doorCount : Integer = 5;
36	attribute groundClearance : LengthValue;
37	attribute roofRails : Boolean = true;
38	}
39	part def TruckBody :> BodyStyle {
40	attribute doorCount : Integer = 4;
41	attribute bedLength : LengthValue;
42	attribute payloadCapacity : MassValue;
43	}
44
45	// ── Powertrain variants ──────────────────────────────────
46	part def Powertrain;
47	part def PetrolPowertrain :> Powertrain {
48	attribute displacement : VolumeValue;
49	attribute cylinders : Integer;
50	attribute maxPower : PowerValue;
51	}
52	part def DieselPowertrain :> Powertrain {
53	attribute displacement : VolumeValue;
54	attribute maxTorque : ForceValue;
55	}
56	part def ElectricPowertrain :> Powertrain {
57	attribute batteryCapacity : EnergyValue;
58	attribute range : LengthValue;
59	attribute chargePower : PowerValue;
60	}
61
62	// ── Optional feature packages (metadata-tagged) ─────────
63	package FeatureCatalog {
64	part heatedSeats : HeatedSeats {
65	@MarketRegion { region = "ALL"; }
66	@FeatureTier { tier = "premium"; }
67	}
68	part adaptiveCruise : AdaptiveCruiseControl {
69	@MarketRegion { region = "ALL"; }
70	@FeatureTier { tier = "premium"; }
71	}
72	part towHitch : TowHitch {
73	@MarketRegion { region = "US"; }
74	@FeatureTier { tier = "basic"; }
75	}
76	part headlightWashers : HeadlightWashers {
77	@MarketRegion { region = "EU"; }
78	@FeatureTier { tier = "basic"; }
79	}
80	}
81
82	// ── Base product with variation points ───────────────────
83	part def Vehicle {
84	// Platform (invariant across all configurations)
85	part chassis : Chassis;
86	part brakes : BrakeSystem;
87	part steering : SteeringSystem;
88
89	// Variation point 1: body style
90	variation part body : BodyStyle {
91	variant part sedan : SedanBody;
92	variant part suv : SUVBody;
93	variant part truck : TruckBody;
94	}
95
96	// Variation point 2: powertrain
97	variation part powertrain : Powertrain {
98	variant part petrol : PetrolPowertrain;
99	variant part diesel : DieselPowertrain;
100	variant part electric : ElectricPowertrain;
101	}
102
103	// Platform constraint: all variants must satisfy
104	assert constraint maxGrossWeight {
105	chassis.curbWeight <= 3000[kg]
106	}
107	}
108
109	// ── Filtered feature views ───────────────────────────────
110	package PremiumFeatures {
111	import FeatureCatalog::**;
112	filter @FeatureTier and FeatureTier::tier == "premium";
113	}
114	package USFeatures {
115	import FeatureCatalog::**;
116	filter @MarketRegion and (MarketRegion::region == "US"
117	or MarketRegion::region == "ALL");
118	}
119	package EUFeatures {
120	import FeatureCatalog::**;
121	filter @MarketRegion and (MarketRegion::region == "EU"
122	or MarketRegion::region == "ALL");
123	}
124
125	// ── Fully resolved configurations ────────────────────────
126	part def SedanPetrolUS :> Vehicle {
127	part body redefines Vehicle::body = body::sedan;
128	part powertrain redefines Vehicle::powertrain = powertrain::petrol;
129	// Include US-market features from the filtered view
130	}
131
132	part def SUVElectricEU :> Vehicle {
133	part body redefines Vehicle::body = body::suv;
134	part powertrain redefines Vehicle::powertrain = powertrain::electric;
135	// Include EU-market features from the filtered view
136	}
137
138	part def TruckDieselUS :> Vehicle {
139	part body redefines Vehicle::body = body::truck;
140	part powertrain redefines Vehicle::powertrain = powertrain::diesel;
141
142	// Truck-specific constraint override
143	assert constraint towRating {
144	body.payloadCapacity >= 1500[kg]
145	}
146	}
147	}