Add unpack method for unpacking integers.

src/code/index.ts

@@ -12,4 +12,5 @@ export * from './span';
 export * from './store';
 export * from './test';
 export * from './update';
+export * from './unpack';
 export * from './value';

src/code/unpack.ts

@@ -0,0 +1,13 @@
+import { Field } from "./field";
+
+export class Unpack extends Field {
+    constructor (
+        name: string, 
+        field:string, 
+        public readonly bigEndian:boolean
+    ){
+        const endian_str = bigEndian ? 'be': 'le';
+        super('match', `unpack_${endian_str}_${field}`, name, field);
+    }
+}
+

src/container/index.ts

@@ -37,6 +37,7 @@ export class Container {
       Store: this.combine((impl) => impl.code.Store),
       Test: this.combine((impl) => impl.code.Test),
       Update: this.combine((impl) => impl.code.Update),
+      Unpack: this.combine((impl) => impl.code.Unpack),
       Value: this.combine((impl) => impl.code.Value),
     };
   }

src/frontend.ts

@@ -470,9 +470,13 @@ export class Frontend {
     } else if (code instanceof source.code.Update) {
       res = new codeImpl.Update(
         new frontend.code.Update(prefixed, code.field, code.value));
-
+
+    } else if (code instanceof source.code.Unpack) {
+      res = new codeImpl.Unpack(
+          new frontend.code.Unpack(prefixed, code.field, code.bigEndian));
+    }
     // External callbacks
-    } else if (code instanceof source.code.Span) {
+    else if (code instanceof source.code.Span) {
       res = new codeImpl.Span(new frontend.code.Span(code.name));
     } else if (code instanceof source.code.Match) {
       res = new codeImpl.Match(new frontend.code.Match(code.name));

src/implementation/code.ts

@@ -11,6 +11,7 @@ export interface ICodeImplementation {
   readonly Span: new(c: code.Span) => IWrap<code.Span>;
   readonly Store: new(c: code.Store) => IWrap<code.Store>;
   readonly Test: new(c: code.Test) => IWrap<code.Test>;
+  readonly Unpack: new(c: code.Unpack) => IWrap<code.Unpack>;
   readonly Update: new(c: code.Update) => IWrap<code.Update>;
   readonly Value: new(c: code.Value) => IWrap<code.Value>;
 }

test/fixtures/a-implementation/code/unpack.ts

@@ -0,0 +1,8 @@
+import { code } from '../../../../src/frontend';
+import { Code } from './base';
+
+export class Unpack extends Code<code.Unpack> {
+  public build(): string {
+    return '';
+  }
+}

test/fixtures/implementation/code/unpack.ts

@@ -0,0 +1,8 @@
+import { code } from '../../../../src/frontend';
+import { Code } from './base';
+
+export class Unpack extends Code<code.Unpack> {
+  public build(): string {
+    return '';
+  }
+}