如何在Typescript中定义带有枚举键的散列

Question

我正在用TypeScript做一个RAM机器模拟器，所以我做了一个RAM可以拥有的指令类型的枚举:

enum InsType {
    LOAD,   // Put value from specified register (or literal) into accumulator.
    STORE,  // Store value from accumulator into specified register.
    READ,   // Read from input tape and write into specified register.
    WRITE,  // Write to output tape from specified register.
    ADD,    // Add value into accumulator.
    SUB,    // Subtract value from accumulator.
    MUL,    // Multiply accumulator by referenced (or literal) value.
    DIV,    // Divide accumulator by referenced (or literal) value.
    HALT,   // Stop program execution.
    JUMP,   // Jump unconditionally to line specified by tag.
    JZERO,  // Jump to line specified by tag if accumulator value is zero.
    JGTZ,   // Jump to line specified by tag if acc value is greater than zero.
}

我必须确保每条指令都有有效的操作数类型。我定义有效操作数的方式如下:

var valid_operands = {
  LOAD:   [OpType.NUM_LITERAL, OpType.NUM_DIRECT, OpType.NUM_INDIRECT],
  STORE:  [                    OpType.NUM_DIRECT, OpType.NUM_INDIRECT],
  READ:   [                    OpType.NUM_DIRECT, OpType.NUM_INDIRECT],
  WRITE:  [OpType.NUM_LITERAL, OpType.NUM_DIRECT, OpType.NUM_INDIRECT],
  ADD:    [OpType.NUM_LITERAL, OpType.NUM_DIRECT, OpType.NUM_INDIRECT],
  SUB:    [OpType.NUM_LITERAL, OpType.NUM_DIRECT, OpType.NUM_INDIRECT],
  MUL:    [OpType.NUM_LITERAL, OpType.NUM_DIRECT, OpType.NUM_INDIRECT],
  DIV:    [OpType.NUM_LITERAL, OpType.NUM_DIRECT, OpType.NUM_INDIRECT],
  HALT:   [OpType.NONE],
  JUMP:   [OpType.NAME],
  JZERO:  [OpType.NAME],
  JGTZ:   [OpType.NAME],
}

但是我发现TypeScript的"编译器"并不关心我在键值中输入了什么——我可以把LOAD:改为LOADXYZ:，它不会眨一下眼睛。

同样，当我试着把它改成:

var valid_operands = {
  InsType.LOAD:   [OpType.NUM_LITERAL, OpType.NUM_DIRECT, OpType.NUM_INDIRECT],
  ...

警告':' expected at line XX col YY(即.的位置)。我正在使用Atom TypeScript插件工作，如果它有帮助的话。

Answer 1

定义[]内部的对象键

var valid_operands = {
  [InsType.LOAD]:   [OpType.NUM_LITERAL, OpType.NUM_DIRECT, OpType.NUM_INDIRECT],
  [InsType.STORE]:  [                    OpType.NUM_DIRECT, OpType.NUM_INDIRECT],

…

Answer 2

您可以使用Map。

enum InsType {
    LOAD,
    STORE
}
enum OpType {
    NUM_LITERAL
}
var vo2 = new Map<InsType, [OpType]>();
vo2.set(InsType.LOAD, [OpType.NUM_LITERAL]);

Answer 3

您可以使用:key in Enum

export let MyHashMap: { [key in KeyType]: IMyObject }

啸:

export enum KeyType {
    A = 'A',
    B = 'B'
}
export interface IMyObject {
    type: KeyType,
    title: string
}
export const MyObject: IMyObject[] = [
    { type: KeyType.A, title: 'my a' },
    { type: KeyType.B, title: 'my b' }
]
//this is the code you want
export let MyHashMap: { [key in KeyType]: IMyObject }

MyHashMap = MyObject.reduce((map, obj) => {
    map[obj.type] = obj;
    return map;
}, {} as { [key in KeyType]: IMyObject });

Answer 4

我解决这个问题的方法是单独分配每个密钥对的值。

var vo2 = { }
vo2[InsType.LOAD]  = [OpType.NUM_LITERAL, OpType.NUM_DIRECT, OpType.NUM_INDIRECT]
vo2[InsType.STORE] = [OpType.NUM_LITERAL, OpType.NUM_DIRECT, OpType.NUM_INDIRECT]
vo2[InsType.READ]  = [OpType.NUM_LITERAL, OpType.NUM_DIRECT, OpType.NUM_INDIRECT]
vo2[InsType.WRITE] = [OpType.NUM_LITERAL, OpType.NUM_DIRECT, OpType.NUM_INDIRECT]
vo2[InsType.ADD]   = [OpType.NUM_LITERAL, OpType.NUM_DIRECT, OpType.NUM_INDIRECT]
vo2[InsType.SUB]   = [OpType.NUM_LITERAL, OpType.NUM_DIRECT, OpType.NUM_INDIRECT]
vo2[InsType.MUL]   = [OpType.NUM_LITERAL, OpType.NUM_DIRECT, OpType.NUM_INDIRECT]
vo2[InsType.DIV]   = [OpType.NUM_LITERAL, OpType.NUM_DIRECT, OpType.NUM_INDIRECT]
vo2[InsType.HALT]  = [OpType.NONE]
vo2[InsType.JUMP]  = [OpType.NAME]
vo2[InsType.JZERO] = [OpType.NAME]
vo2[InsType.JGTZ]  = [OpType.NAME]

很好。但是如果有人找到了一种方法来声明一个枚举键的哈希值，请继续并发布答案。:)