Introduce round brackets for multi-valued filter operands

Allowing us to drop the varlist operator

core/modules/filters.js

@@ -38,7 +38,7 @@ function parseFilterOperation(operators,filterString,p) {
 			operator.prefix = filterString.charAt(p++);
 		}
 		// Get the operator name
-		nextBracketPos = filterString.substring(p).search(/[\[\{<\/]/);
+		nextBracketPos = filterString.substring(p).search(/[\[\{<\/\(]/);
 		if(nextBracketPos === -1) {
 			throw "Missing [ in filter expression";
 		}
@@ -82,6 +82,10 @@ function parseFilterOperation(operators,filterString,p) {
 					operand.variable = true;
 					nextBracketPos = filterString.indexOf(">",p);
 					break;
+				case "(": // Round brackets
+					operand.multiValuedVariable = true;
+					nextBracketPos = filterString.indexOf(")",p);
+					break;
 				case "/": // regexp brackets
 					var rex = /^((?:[^\\\/]|\\.)*)\/(?:\(([mygi]+)\))?/g,
 						rexMatch = rex.exec(filterString.substring(p));
@@ -255,6 +259,8 @@ exports.compileFilter = function(filterString) {
 				currTiddlerTitle = widget && widget.getVariable("currentTiddler");
 			$tw.utils.each(operation.operators,function(operator) {
 				var operands = [],
+					multiValueOperands = [],
+					isMultiValueOperand = [],
 					operatorFunction;
 				if(!operator.operator) {
 					// Use the "title" operator if no operator is specified
@@ -269,13 +275,29 @@ exports.compileFilter = function(filterString) {
 				$tw.utils.each(operator.operands,function(operand) {
 					if(operand.indirect) {
 						operand.value = self.getTextReference(operand.text,"",currTiddlerTitle);
+						operand.multiValue = [operand.value];
 					} else if(operand.variable) {
 						var varTree = $tw.utils.parseFilterVariable(operand.text);
 						operand.value = widgetClass.evaluateVariable(widget,varTree.name,{params: varTree.params, source: source})[0] || "";
+						operand.multiValue = [operand.value];
+					} else if(operand.multiValuedVariable) {
+						var varTree = $tw.utils.parseFilterVariable(operand.text);
+						var resultList = widgetClass.evaluateVariable(widget,varTree.name,{params: varTree.params, source: source});
+						if((resultList.length > 0 && resultList[0] !== undefined) || resultList.length === 0) {
+							operand.multiValue = widgetClass.evaluateVariable(widget,varTree.name,{params: varTree.params, source: source}) || [];
+							operand.value = operand.multiValue[0] || "";
+						} else {
+							operand.value = "";
+							operand.multiValue = [];
+						}
+						operand.isMultiValueOperand = true;	
 					} else {
 						operand.value = operand.text;
+						operand.multiValue = [operand.value];
 					}
 					operands.push(operand.value);
+					multiValueOperands.push(operand.multiValue);
+					isMultiValueOperand.push(!!operand.isMultiValueOperand);
 				});
 
 				// Invoke the appropriate filteroperator module
@@ -283,6 +305,8 @@ exports.compileFilter = function(filterString) {
 							operator: operator.operator,
 							operand: operands.length > 0 ? operands[0] : undefined,
 							operands: operands,
+							multiValueOperands: multiValueOperands,
+							isMultiValueOperand: isMultiValueOperand,
 							prefix: operator.prefix,
 							suffix: operator.suffix,
 							suffixes: operator.suffixes,

core/modules/filters/title.js

@@ -24,7 +24,11 @@ exports.title = function(source,operator,options) {
 			}
 		});
 	} else {
-		results.push(operator.operand);
+		if(operator.isMultiValueOperand[0]) {
+			Array.prototype.push.apply(results,operator.multiValueOperands[0]);
+		} else {
+			results.push(operator.operand);
+		}
 	}
 	return results;
 };

core/modules/filters/varlist.js

@@ -1,27 +0,0 @@
-/*\
-title: $:/core/modules/filters/varlist.js
-type: application/javascript
-module-type: filteroperator
-
-Retrieve the value of a variable as a list
-
-\*/
-(function(){
-
-/*jslint node: true, browser: true */
-/*global $tw: false */
-"use strict";
-
-/*
-Export our filter function
-*/
-exports.varlist = function(source,operator,options) {
-	var variableInfo = operator.operand && options.widget.getVariableInfo(operator.operand);
-	if(variableInfo && variableInfo.text !== undefined) {
-		return options.wiki.makeTiddlerIterator(variableInfo.resultList);
-	} else {
-		return [];
-	}
-};
-
-})();

editions/prerelease/tiddlers/system/DefaultTiddlers.tid

@@ -2,6 +2,5 @@ created: 20131127215321439
 modified: 20140912135951542
 title: $:/DefaultTiddlers
 
+[[Multi-Valued Variables]]
 [[Let Filter Run Prefix]]
-[[varlist Operator]]
-[[LetListWidget]]

editions/test/tiddlers/tests/data/let-filter-prefix/ResultList.tid

@@ -5,7 +5,7 @@ tags: [[$:/tags/wiki-test-spec]]
 
 title: Output
 
-<$text text={{{ [all[tiddlers]] :let[[varname]] [varlist[varname]sort[]join[,]] }}}/>
+<$text text={{{ [all[tiddlers]] :let[[varname]] [(varname)sort[]join[,]] }}}/>
 +
 title: ExpectedResult
 

editions/test/tiddlers/tests/data/let-filter-prefix/ResultListUnnamedVariable.tid

@@ -5,7 +5,7 @@ tags: [[$:/tags/wiki-test-spec]]
 
 title: Output
 
-<$text text={{{ [all[tiddlers]] :let[all[]tag[nothing]] [varlist[varname]sort[]join[,]] }}}/>
+<$text text={{{ [all[tiddlers]] :let[all[]tag[nothing]] [(varname)sort[]join[,]] }}}/>
 +
 title: ExpectedResult
 

editions/test/tiddlers/tests/data/multi-valued-variables/MissingVariable.tid

@@ -1,11 +1,11 @@
 title: MultiValuedVariables/MissingVariable
-description: Using varlist with a missing variable
+description: Using multivalued operands with a missing variable
 type: text/vnd.tiddlywiki-multiple
 tags: [[$:/tags/wiki-test-spec]]
 
 title: Output
 
-<$text text={{{ [varlist[varname]] }}}/>
+<$text text={{{ [(varname)] }}}/>
 +
 title: ExpectedResult
 

editions/test/tiddlers/tests/data/multi-valued-variables/MultiValuedFunction.tid

@@ -8,7 +8,7 @@ title: Output
 \function myfunc() [all[tiddlers]sort[]]
 
 <$let varname=<<myfunc>>>
-<$text text={{{ [varlist[varname]] +[join[-]] }}}/>
+<$text text={{{ [(varname)] +[join[-]] }}}/>
 </$let>
 +
 title: ExpectedResult

editions/test/tiddlers/tests/data/multi-valued-variables/MultiValuedOperands.tid

@@ -0,0 +1,18 @@
+title: MultiValuedVariables/Operands
+description: Multi-valued operands
+type: text/vnd.tiddlywiki-multiple
+tags: [[$:/tags/wiki-test-spec]]
+
+title: Output
+
+\function myfunc() [all[tiddlers]sort[]]
+
+<$let varname=<<myfunc>>>
+<$text text={{{ [(varname)] +[join[-]] }}}/>
+</$let>
++
+title: ExpectedResult
+
+<p>
+$:/core-ExpectedResult-Output
+</p>

editions/test/tiddlers/tests/data/multi-valued-variables/Simple.tid

@@ -7,7 +7,7 @@ title: Output
 
 <$let varname={{{ [all[tiddlers]sort[]] }}}
 	varname2=<<varname>>>
-<$text text={{{ [varlist[varname2]] +[join[-]] }}}/>
+<$text text={{{ [(varname2)] +[join[-]] }}}/>
 </$let>
 +
 title: ExpectedResult

editions/tw5.com/tiddlers/filters/syntax/Let Filter Run Prefix.tid

@@ -17,6 +17,6 @@ type: text/vnd.tiddlywiki
 
 The `:let` filter run prefix assigns the title list resulting from previous filter runs to a [[multi-valued variable|Multi-Valued Variable]]. The variable is named with the first result returned by the filter run.
 
-The variable is made available to the remaining [[filter runs|Filter Run]] in the [[filter expression|Filter Expression]]. Only the first item in the result list is returned when the variable is accessed in the usual way (or an empty string if the result list is empty). The special [varlist Operator] is used to access all the items in the result list.
+The variable is made available to the remaining [[filter runs|Filter Run]] in the [[filter expression|Filter Expression]]. Only the first item in the result list is returned when the variable is accessed in the usual way (or an empty string if the result list is empty). Using round brackets instead of angle brackets around a variable name as an operand retrieves the complete list of items in the result list.
 
 The `:let` filter run prefix always clears the current result list.

editions/tw5.com/tiddlers/filters/varlist Operator.tid

@@ -1,14 +0,0 @@
-caption: varlist
-created: 20250307212252946
-modified: 20250307212252946
-op-input: ignored
-op-output: the list items stored in the variable
-op-parameter: the name of a variable
-op-purpose: retrieve the value of a variable as a list
-tags: [[Filter Operators]] [[Selection Constructors]]
-title: varlist Operator
-type: text/vnd.tiddlywiki
-
-<<.from-version "5.3.7">> The parameter specifies the name of a variable that has been assigned a list of items by a [[let filter run prefix|Let Filter Run Prefix]]. The operator retrieves all the list items stored in the variable.
-
-<<.operator-examples "varlist">>

editions/tw5.com/tiddlers/system/DefaultTiddlers.tid

@@ -3,6 +3,5 @@ modified: 20140912135951542
 title: $:/DefaultTiddlers
 type: text/vnd.tiddlywiki
 
+[[Multi-Valued Variables]]
 [[Let Filter Run Prefix]]
-[[varlist Operator]]
-[[LetListWidget]]

editions/tw5.com/tiddlers/variables/Multi-Valued Variables.tid

@@ -3,14 +3,14 @@ created: 20250307212252946
 modified: 20250307212252946
 tags: Concepts Variables
 
-<<.from-version "5.3.7">> In ordinary usage, [[variables|Variables]] contain a single spinnet of text. With the introduction of multi-valued variables. it is now possible to store a list of multiple values in a single variable. When accessed in the usual way, only the first value is returned, but the [[varlist Operator]] can be used to access all the values. This makes the existence of multi-valued variables largely invisible unless you specifically need to use them.
+<<.from-version "5.3.7">> In ordinary usage, [[variables|Variables]] contain a single spinnet of text. With the introduction of multi-valued variables. it is now possible to store a list of multiple values in a single variable. When accessed in the usual way, only the first value is returned, but using round brackets instead of angle brackets around the variable name allows access to the complete list of the values. This makes the existence of multi-valued variables largely invisible unless you specifically need to use them.
 
 The <<.wid let>> widget also allows [[multi-valued variables|Multi-Valued Variables]] to be set in one operation, each to the complete list of results obtained from evaluating an attribute.
 
 For example:
 
 ```
-<$letlist varname={{{ [all[tiddlers]sort[]] }}}>
-<$text text={{{ [varlist[varname]] +[join[-]] }}}/>
-</$letlist>
+<$let varname={{{ [all[tiddlers]sort[]] }}}>
+<$text text={{{ [(varname)] +[join[-]] }}}/>
+</$let>
 ```

editions/tw5.com/tiddlers/variables/Variables.tid

@@ -9,7 +9,7 @@ type: text/vnd.tiddlywiki
 * A <<.def variable>> is a ''snippet of text'' that can be accessed by name
 * The text is referred to as the variable's <<.def value>>
 
-<<.from-version "5.3.7">> In ordinary usage, variables contain a single spinnet of text. With the introduction of [[Multi-Valued Variables]] it is now possible to store a list of multiple values in a single variable. When accessed in the usual way, only the first value is returned, but the [[varlist Operator]] can be used to access all the values. This makes the existence of multi-valued variables largely invisible unless you specifically need to use them
+<<.from-version "5.3.7">> In ordinary usage, variables contain a single spinnet of text. With the introduction of [[Multi-Valued Variables]] it is now possible to store a list of multiple values in a single variable. When accessed in the usual way, only the first value is returned, but using round brackets instead of the usual angle brackets retrieves the complete list of values. This makes the existence of multi-valued variables largely invisible unless you specifically need to use them.
 
 Variables are defined by [[widgets|Widgets]]. Several core widgets define variables, the most common being the <<.wlink LetWidget>>, <<.wlink SetWidget>> and <<.wlink ListWidget>> widgets.
 

editions/tw5.com/tiddlers/widgets/LetWidget.tid

@@ -23,12 +23,12 @@ Attributes are evaluated in the order they are written. Attributes with the same
 
 <<.from-version "5.3.7">> The <<.wid let>> widget also allows [[multi-valued variables|Multi-Valued Variables]] to be set in one operation, each to the complete list of results obtained from evaluating an attribute.
 
-Almost all operations that work with variables only consider the first item in the list. The [[varlist Operator]] gives access to the complete list of results. For example:
+Almost all operations that work with variables only consider the first item in the list. Using round brackets instead of angle brackets around the variable name gives access to the complete list of results. For example:
 
 ```
-<$letlist varname={{{ [all[tiddlers]sort[]] }}}>
-<$text text={{{ [varlist[varname]] +[join[-]] }}}/>
-</$letlist>
+<$let varname={{{ [all[tiddlers]sort[]] }}}>
+<$text text={{{ [(varname)] +[join[-]] }}}/>
+</$let>
 ```
 
 ! Examples