Add ArrayBuffer/DataView/Symbol#toString and improve Errors (#332)

Author: MaxGraey

std/assembly/arraybuffer.ts

@@ -30,4 +30,8 @@ export class ArrayBuffer {
     memory.copy(changetype<usize>(buffer) + HEADER_SIZE, changetype<usize>(this) + HEADER_SIZE + begin, newLen);
     return buffer;
   }
+
+  toString(): string {
+    return "[object ArrayBuffer]";
+  }
 }

std/assembly/dataview.ts

@@ -177,6 +177,10 @@ export class DataView {
       HEADER_SIZE
     );
   }
+
+  toString(): string {
+    return "[object DataView]";
+  }
 }
 
 @inline function checkOffset(byteOffset: i32, n: i32, byteLength: i32): void {

std/assembly/error.ts

@@ -1,12 +1,11 @@
 export class Error {
 
-  name: string = "Error";
-  message: string;
+  name: string  = "Error";
   stack: string = ""; // TODO
 
-  constructor(message: string = "") {
-    this.message = message;
-  }
+  constructor(
+    public message: string = ""
+  ) {}
 
   toString(): string {
     var message = this.message;
@@ -29,3 +28,10 @@ export class TypeError extends Error {
     this.name = "TypeError";
   }
 }
+
+export class SyntaxError extends Error {
+  constructor(message: string = "") {
+    super(message);
+    this.name = "SyntaxError";
+  }
+}

std/assembly/index.d.ts

@@ -447,45 +447,47 @@ declare class DataView {
   /** Constructs a new `DataView` with the given properties */
   constructor(buffer: ArrayBuffer, byteOffset?: i32, byteLength?: i32);
   /** The `getFloat32()` method gets a signed 32-bit float (float) at the specified byte offset from the start of the `DataView`. */
-  getFloat32(byteOffset: i32, littleEndian?: boolean): f32
+  getFloat32(byteOffset: i32, littleEndian?: boolean): f32;
   /** The `getFloat64()` method gets a signed 64-bit float (double) at the specified byte offset from the start of the `DataView`. */
-  getFloat64(byteOffset: i32, littleEndian?: boolean): f64
+  getFloat64(byteOffset: i32, littleEndian?: boolean): f64;
   /** The `getInt8()` method gets a signed 8-bit integer (byte) at the specified byte offset from the start of the `DataView`. */
-  getInt8(byteOffset: i32): i8
+  getInt8(byteOffset: i32): i8;
   /** The `getInt16()` method gets a signed 16-bit integer (short) at the specified byte offset from the start of the `DataView`. */
-  getInt16(byteOffset: i32, littleEndian?: boolean): i16
+  getInt16(byteOffset: i32, littleEndian?: boolean): i16;
   /** The `getInt32()` method gets a signed 32-bit integer (long) at the specified byte offset from the start of the `DataView`. */
-  getInt32(byteOffset: i32, littleEndian?: boolean): i32
+  getInt32(byteOffset: i32, littleEndian?: boolean): i32;
   /** The `getInt64()` method gets a signed 64-bit integer (long long) at the specified byte offset from the start of the `DataView`. */
-  getInt64(byteOffset: i32, littleEndian?: boolean): i64
+  getInt64(byteOffset: i32, littleEndian?: boolean): i64;
   /** The `getUint8()` method gets an unsigned 8-bit integer (unsigned byte) at the specified byte offset from the start of the `DataView`. */
-  getUint8(byteOffset: i32): u8
+  getUint8(byteOffset: i32): u8;
   /** The `getUint16()` method gets an unsigned 16-bit integer (unsigned short) at the specified byte offset from the start of the `DataView`. */
-  getUint16(byteOffset: i32, littleEndian?: boolean): u16
+  getUint16(byteOffset: i32, littleEndian?: boolean): u16;
   /** The `getUint32()` method gets an unsigned 32-bit integer (unsigned long) at the specified byte offset from the start of the `DataView`. */
-  getUint32(byteOffset: i32, littleEndian?: boolean): u32
+  getUint32(byteOffset: i32, littleEndian?: boolean): u32;
   /** The `getUint64()` method gets an unsigned 64-bit integer (unsigned long long) at the specified byte offset from the start of the `DataView`. */
-  getUint64(byteOffset: i32, littleEndian?: boolean): u64
+  getUint64(byteOffset: i32, littleEndian?: boolean): u64;
   /** The `setFloat32()` method stores a signed 32-bit float (float) value at the specified byte offset from the start of the `DataView`. */
-  setFloat32(byteOffset: i32, value: f32, littleEndian?: boolean): void
+  setFloat32(byteOffset: i32, value: f32, littleEndian?: boolean): void;
   /** The `setFloat64()` method stores a signed 64-bit float (double) value at the specified byte offset from the start of the `DataView`. */
-  setFloat64(byteOffset: i32, value: f64, littleEndian?: boolean): void
+  setFloat64(byteOffset: i32, value: f64, littleEndian?: boolean): void;
   /** The `setInt8()` method stores a signed 8-bit integer (byte) value at the specified byte offset from the start of the `DataView`. */
-  setInt8(byteOffset: i32, value: i8): void
+  setInt8(byteOffset: i32, value: i8): void;
   /** The `setInt16()` method stores a signed 16-bit integer (short) value at the specified byte offset from the start of the `DataView`. */
-  setInt16(byteOffset: i32, value: i16, littleEndian?: boolean): void
+  setInt16(byteOffset: i32, value: i16, littleEndian?: boolean): void;
   /** The `setInt32()` method stores a signed 32-bit integer (long) value at the specified byte offset from the start of the `DataView`. */
-  setInt32(byteOffset: i32, value: i32, littleEndian?: boolean): void
+  setInt32(byteOffset: i32, value: i32, littleEndian?: boolean): void;
   /** The `setInt64()` method stores a signed 64-bit integer (long long) value at the specified byte offset from the start of the `DataView`. */
-  setInt64(byteOffset: i32, value: i64, littleEndian?: boolean): void
+  setInt64(byteOffset: i32, value: i64, littleEndian?: boolean): void;
   /** The `setUint8()` method stores an unsigned 8-bit integer (byte) value at the specified byte offset from the start of the `DataView`. */
-  setUint8(byteOffset: i32, value: u8): void
+  setUint8(byteOffset: i32, value: u8): void;
   /** The `setUint16()` method stores an unsigned 16-bit integer (unsigned short) value at the specified byte offset from the start of the `DataView`. */
-  setUint16(byteOffset: i32, value: u16, littleEndian?: boolean): void
+  setUint16(byteOffset: i32, value: u16, littleEndian?: boolean): void;
   /** The `setUint32()` method stores an unsigned 32-bit integer (unsigned long) value at the specified byte offset from the start of the `DataView`. */
-  setUint32(byteOffset: i32, value: u32, littleEndian?: boolean): void
+  setUint32(byteOffset: i32, value: u32, littleEndian?: boolean): void;
   /** The `setUint64()` method stores an unsigned 64-bit integer (unsigned long long) value at the specified byte offset from the start of the `DataView`. */
-  setUint64(byteOffset: i32, value: u64, littleEndian?: boolean): void
+  setUint64(byteOffset: i32, value: u64, littleEndian?: boolean): void;
+  /** Returns a string representation of DataView. */
+  toString(): string;
 }
 
 /** Interface for a typed view on an array buffer. */
@@ -621,15 +623,24 @@ declare class Error {
   message: string;
 
   /** Stack trace. */
-  stack: string;
+  stack?: string;
 
   /** Constructs a new error, optionally with a message. */
   constructor(message?: string);
+
+  /** Method returns a string representing the specified Error class. */
+  toString(): string;
 }
 
 /** Class for indicating an error when a value is not in the set or range of allowed values. */
 declare class RangeError extends Error { }
 
+/** Class for indicating an error when a value is not of the expected type. */
+declare class TypeError extends Error { }
+
+/** Class for indicating an error when trying to interpret syntactically invalid code. */
+declare class SyntaxError extends Error { }
+
 interface Boolean {}
 interface Function {}
 interface IArguments {}
@@ -644,6 +655,7 @@ declare class Map<K,V> {
   get(key: K): V;
   delete(key: K): bool;
   clear(): void;
+  toString(): string;
 }
 
 declare class Set<T> {
@@ -652,13 +664,27 @@ declare class Set<T> {
   add(value: T): void;
   delete(value: T): bool;
   clear(): void;
+  toString(): string;
 }
 
 interface SymbolConstructor {
+  readonly hasInstance: symbol;
+  readonly isConcatSpreadable: symbol;
+  readonly isRegExp: symbol;
+  readonly iterator: symbol;
+  readonly match: symbol;
+  readonly replace: symbol;
+  readonly search: symbol;
+  readonly species: symbol;
+  readonly split: symbol;
+  readonly toPrimitive: symbol;
+  readonly toStringTag: symbol;
+  readonly unscopables: symbol;
   (description?: string | null): symbol;
   for(key: string): symbol;
   keyFor(sym: symbol): string | null;
 }
+
 declare const Symbol: SymbolConstructor;
 
 interface IMath<T> {

std/assembly/map.ts

@@ -165,6 +165,10 @@ export class Map<K,V> {
     this.entriesOffset = this.entriesCount;
   }
 
+  toString(): string {
+    return "[object Map]";
+  }
+
   private __gc(): void {
     __gc_mark(changetype<usize>(this.buckets)); // tslint:disable-line
     var entries = this.entries;

std/assembly/set.ts

@@ -153,6 +153,10 @@ export class Set<K> {
     this.entriesOffset = this.entriesCount;
   }
 
+  toString(): string {
+    return "[object Set]";
+  }
+
   private __gc(): void {
     __gc_mark(changetype<usize>(this.buckets)); // tslint:disable-line
     var entries = this.entries;

std/assembly/symbol.ts

@@ -4,7 +4,30 @@ var stringToId: Map<string, usize>;
 var idToString: Map<usize, string>;
 var nextId: usize = 12; // Symbol.unscopables + 1
 
-@unmanaged export class symbol {}
+@unmanaged export class symbol {
+  toString(): string {
+    var id = changetype<usize>(this);
+    var str = "";
+    switch (id) {
+      case 1:  { str = "hasInstance"; break; }
+      case 2:  { str = "isConcatSpreadable"; break; }
+      case 3:  { str = "isRegExp"; break; }
+      case 4:  { str = "match"; break; }
+      case 5:  { str = "replace"; break; }
+      case 6:  { str = "search"; break; }
+      case 7:  { str = "species"; break; }
+      case 8:  { str = "split"; break; }
+      case 9:  { str = "toPrimitive"; break; }
+      case 10: { str = "toStringTag"; break; }
+      case 11: { str = "unscopables"; break; }
+      default: {
+        if (idToString !== null && idToString.has(id)) str = idToString.get(id);
+        break;
+      }
+    }
+    return "Symbol(" + str + ")";
+  }
+}
 
 type Symbol = symbol;
 
@@ -17,18 +40,18 @@ export function Symbol(description: string | null = null): symbol {
 export namespace Symbol {
 
   // well-known symbols
-  export const hasInstance      = changetype<symbol>(1);
-  export const concatSpreadable = changetype<symbol>(2);
-  export const isRegExp         = changetype<symbol>(3);
-  export const iterator         = changetype<symbol>(3);
-  export const match            = changetype<symbol>(4);
-  export const replace          = changetype<symbol>(5);
-  export const search           = changetype<symbol>(6);
-  export const species          = changetype<symbol>(7);
-  export const split            = changetype<symbol>(8);
-  export const toPrimitive      = changetype<symbol>(9);
-  export const toStringTag      = changetype<symbol>(10);
-  export const unscopables      = changetype<symbol>(11);
+  export const hasInstance        = changetype<symbol>(1);
+  export const isConcatSpreadable = changetype<symbol>(2);
+  export const isRegExp           = changetype<symbol>(3);
+  export const iterator           = changetype<symbol>(3);
+  export const match              = changetype<symbol>(4);
+  export const replace            = changetype<symbol>(5);
+  export const search             = changetype<symbol>(6);
+  export const species            = changetype<symbol>(7);
+  export const split              = changetype<symbol>(8);
+  export const toPrimitive        = changetype<symbol>(9);
+  export const toStringTag        = changetype<symbol>(10);
+  export const unscopables        = changetype<symbol>(11);
 
   /* tslint:disable */// not valid TS
   export function for(key: string): symbol {