From 4d42968cd6deec8b3824b45b36e954765f1acb2b Mon Sep 17 00:00:00 2001
From: Tony Garnock-Jones <tonyg@leastfixedpoint.com>
Date: Mon, 13 Dec 2021 12:20:51 +0100
Subject: [PATCH] Repair an error and a couple of infelicities in quasivalue.ts

---
 packages/core/src/runtime/quasivalue.ts | 29 ++++++++++++++++++-------
 1 file changed, 21 insertions(+), 8 deletions(-)

diff --git a/packages/core/src/runtime/quasivalue.ts b/packages/core/src/runtime/quasivalue.ts
index 1eaa899..aa89b2a 100644
--- a/packages/core/src/runtime/quasivalue.ts
+++ b/packages/core/src/runtime/quasivalue.ts
@@ -4,7 +4,7 @@
 import { AnyValue, Ref } from './actor.js';
 import { Pattern } from '../gen/dataspacePatterns.js';
 import * as P from './pattern.js';
-import { Value, RecordConstructorInfo, is } from '@preserves/core';
+import { Value, RecordConstructorInfo, is, Record } from '@preserves/core';
 import { Meta, Type, GenType } from '@preserves/schema';
 
 export type DefinitionOrVariantInfo = {
@@ -33,7 +33,7 @@ export function bind(p?: QuasiValue): QuasiValue {
     return { type: 'bind', inner: p ?? _ };
 }
 
-bind.quasiValue = (inner: QuasiValue) => rec(Symbol.for('bind'), inner);
+bind.quasiValue = (inner?: QuasiValue) => rec(Symbol.for('bind'), inner ?? _);
 
 export function discard(): QuasiValue {
     return { type: 'discard' };
@@ -50,11 +50,21 @@ export function lit(value: AnyValue): QuasiValue {
 lit.quasiValue = (q: QuasiValue) => rec(Symbol.for('lit'), q);
 
 export function rec(label: AnyValue, ... items: QuasiValue[]): QuasiValue {
-    return { type: 'rec', label, items };
+    const literals = items.flatMap(i => i.type === 'lit' ? [i.value] : []);
+    if (literals.length === items.length) {
+        return lit(Record(label, literals));
+    } else {
+        return { type: 'rec', label, items };
+    }
 }
 
 export function arr(... items: QuasiValue[]): QuasiValue {
-    return { type: 'arr', items };
+    const literals = items.flatMap(i => i.type === 'lit' ? [i.value] : []);
+    if (literals.length === items.length) {
+        return lit(literals);
+    } else {
+        return { type: 'arr', items };
+    }
 }
 
 export function dict(... entries: [AnyValue, QuasiValue][]): QuasiValue {
@@ -194,10 +204,13 @@ export function ctor(info: QuasiValueConstructorInfo, ... items: QuasiValue[]):
         }
 
         function qArr(q: QuasiValue): QuasiValue[] {
-            if (q.type !== 'arr') {
+            if (q.type === 'arr') {
+                return q.items;
+            } else if (q.type === 'lit' && Array.isArray(q.value)) {
+                return q.value.map(lit);
+            } else {
                 throw new Error("Array of quasivalues needed");
             }
-            return q.items;
         }
 
         switch (def._variant) {
@@ -226,9 +239,9 @@ export function ctor(info: QuasiValueConstructorInfo, ... items: QuasiValue[]):
 
 export function finish(q: QuasiValue): Pattern {
     // console.log('--------------------------');
-    // console.log(require('util').inspect(q, {depth: null}));
+    // console.log(q);
     const p = walk(q);
-    // console.log(stringify(fromPattern(p)))
+    // console.log(p);
     return p;
 }