Replace StringRange w/ an actual StrRVal + more command implementations

src/vm/commands/unique.ts

@@ -1,5 +1,7 @@
-import {Command, ParseContext} from "./command.js";
+import {Command, hashStrRVal, ParseContext, unwrapDestructured, wrapDestructured, wrapString} from "./command.js";
 import {LexInput} from "../lexer.js";
+import {StrVM} from "../vm.js";
+import {Awaitable} from "../../util/types.js";
 
 export class Unique extends Command<{}> {
     isParseCandidate(token: LexInput): boolean {
@@ -13,4 +15,22 @@ export class Unique extends Command<{}> {
     getDisplayName(): string {
         return 'unique'
     }
+
+    execute(vm: StrVM): Awaitable<StrVM> {
+        return vm.tapInPlace(ctx =>
+            ctx.replaceSubject(sub => {
+                const seen: Record<string, boolean> = {}
+                return wrapDestructured(
+                    unwrapDestructured(sub)
+                        .filter(part => {
+                            const hash = hashStrRVal(wrapString(part.value))
+                            if ( seen[hash] ) {
+                                return false
+                            }
+
+                            seen[hash] = true
+                            return true
+                        }))
+            }))
+    }
 }