Add tuple operations to index.d.ts and README.md (#31)

Author: drew-y

README.md

@@ -445,7 +445,7 @@ API
 
 * Module#**loop**(label: `string | null`, body: `ExpressionRef`): `ExpressionRef`<br />
   Creates a loop.
-  
+
 * Module#**br**(label: `string`, condition?: `ExpressionRef`, value?: `ExpressionRef`): `ExpressionRef`<br />
   Creates a branch (br) to a label.
 
@@ -974,6 +974,8 @@ Note that these are pseudo instructions enabling Binaryen to reason about multip
 * Module#anyref.**pop**(): `ExpressionRef`
 * Module#nullref.**pop**(): `ExpressionRef`
 * Module#exnref.**pop**(): `ExpressionRef`
+* Module#tuple.**make**(elements: `ExpressionRef[]`): `ExpressionRef`
+* Module#tuple.**extract**(tuple: `ExpressionRef`, index: `number`): `ExpressionRef`
 
 #### [Exception handling operations](https://github.com/WebAssembly/exception-handling/blob/master/proposals/Exceptions.md) 🦄
 
@@ -1170,7 +1172,7 @@ Note that these are pseudo instructions enabling Binaryen to reason about multip
   * SIMDShuffleInfo#**left**: `ExpressionRef`
   * SIMDShuffleInfo#**right**: `ExpressionRef`
   * SIMDShuffleInfo#**mask**: `Uint8Array`
-  > 
+  >
   * SIMDTernaryInfo#**op**: `Op`
   * SIMDTernaryInfo#**a**: `ExpressionRef`
   * SIMDTernaryInfo#**b**: `ExpressionRef`

index.d.ts

@@ -67,6 +67,8 @@ declare module binaryen {
     Throw,
     Rethrow,
     BrOnExn,
+    TupleMake,
+    TupleExtract,
     Push,
     Pop
   }
@@ -116,6 +118,8 @@ declare module binaryen {
   const ThrowId: ExpressionIds;
   const RethrowId: ExpressionIds;
   const BrOnExnId: ExpressionIds;
+  const TupleMakeId: ExpressionIds;
+  const TupleExtractId: ExpressionIds;
   const PushId: ExpressionIds;
   const PopId: ExpressionIds;
 
@@ -1338,6 +1342,10 @@ declare module binaryen {
       notify(ptr: ExpressionRef, notifyCount: ExpressionRef): ExpressionRef;
       fence(): ExpressionRef;
     };
+    tuple: {
+      make(elements: ExportRef[]): ExpressionRef;
+      extract(tuple: ExpressionRef, index: number): ExpressionRef;
+    };
     try(body: ExpressionRef, catchBody: ExpressionRef): ExpressionRef;
     throw(event: string, operands: ExpressionRef[]): ExpressionRef;
     rethrow(exnref: ExpressionRef): ExpressionRef;