added arity control for assembling polyadic inputs

HISTORY.md

@@ -3,6 +3,7 @@
 ## in development:
 
 * **New Features:**
+    * arity control for assembling polyadic inputs using JOIN (pass a list whose first item is an integer representing the number of slots followed by the contents of those slots)
 * **Notable Changes:**
     * same blocks with empty variadic inputs compare as equal regardless of their arity
     * made "When I receive any messagge" non-thread-safe by default (again) to enable tail recursive broadcasts
@@ -20,6 +21,7 @@
 
 ### 2022-01-04
 * manifest: fixed #2954
+* threads, blocks: added arity control for assembling polyadic inputs
 
 ### 2022-01-03
 * Italian translation update, thanks, Stefano!

snap.html

@@ -16,8 +16,8 @@
         <script src="src/morphic.js?version=2021-12-10"></script>
         <script src="src/symbols.js?version=2021-03-03"></script>
         <script src="src/widgets.js?version=2021-17-09"></script>
-        <script src="src/blocks.js?version=2021-12-20"></script>
-        <script src="src/threads.js?version=2022-01-02"></script>
+        <script src="src/blocks.js?version=2022-01-04"></script>
+        <script src="src/threads.js?version=2022-01-04"></script>
         <script src="src/objects.js?version=2022-01-03"></script>
         <script src="src/scenes.js?version=2021-11-24"></script>
         <script src="src/gui.js?version=2021-12-22"></script>

src/blocks.js

@@ -9,7 +9,7 @@
     written by Jens Mönig
     jens@moenig.org
 
-    Copyright (C) 2021 by Jens Mönig
+    Copyright (C) 2022 by Jens Mönig
 
     This file is part of Snap!.
 
@@ -160,7 +160,7 @@ CustomCommandBlockMorph, ToggleButtonMorph, DialMorph, SnapExtensions*/
 
 // Global stuff ////////////////////////////////////////////////////////
 
-modules.blocks = '2021-December-20';
+modules.blocks = '2022-January-04';
 
 var SyntaxElementMorph;
 var BlockMorph;
@@ -3849,7 +3849,7 @@ BlockMorph.prototype.copyWithInputs = function (inputs) {
     // distribute inputs among the slots
     slots = cpy.inputs();
     slots.forEach((slot) => {
-        var inp;
+        var inp, i, cnt;
         if (slot instanceof MultiArgMorph && slot.inputs().length) {
             slot.inputs().forEach(entry => {
                 inp = dta[count];
@@ -3885,8 +3885,26 @@ BlockMorph.prototype.copyWithInputs = function (inputs) {
                     slot.nestedBlock(inp);
                 }
             } else {
-                if (inp instanceof List && inp.length() === 0) {
-                    nop(); // ignore, i.e. leave slot as is
+                if (inp instanceof List) {
+                    if (inp.length() === 0) {
+                        nop(); // ignore, i.e. leave slot as is
+                    } else if (slot instanceof MultiArgMorph) {
+                        slot.collapseAll();
+                        for (i = 1; i <= inp.at(1); i += 1) {
+                            cnt = inp.at(i + 1);
+                            if (cnt instanceof List) {
+                                cnt = Process.prototype.assemble(cnt);
+                            }
+                            if (cnt instanceof Context) {
+                                slot.replaceInput(
+                                    slot.addInput(),
+                                    cnt.expression.fullCopy()
+                                );
+                            } else {
+                                slot.addInput(cnt);
+                            }
+                        }
+                    }
                 } else if (slot instanceof ColorSlotMorph) {
                     slot.setColor(Color.fromString(inp));
                 } else if (slot instanceof InputSlotMorph ||

src/threads.js

@@ -64,7 +64,7 @@ SnapExtensions, AlignmentMorph, TextMorph, Cloud, HatBlockMorph*/
 
 /*jshint esversion: 6*/
 
-modules.threads = '2022-January-03';
+modules.threads = '2022-January-04';
 
 var ThreadManager;
 var Process;
@@ -4574,6 +4574,9 @@ Process.prototype.assemble = function (blocks) {
     if (blocks.isEmpty()) {
         return blocks;
     }
+    if (this.reportIsA(blocks.at(1), 'number')) {
+        return blocks.map(each => this.assemble(each));
+    }
     return blocks.map(each => this.assemble(each)).itemsArray().reduce(
         (a, b) => a.copyWithNext(b)
     );