Get rid of the special behaviour for all[]

Not needed because the input to the filter run is available

core/modules/filterrunprefixes/let.js

@@ -20,11 +20,9 @@ exports.let = function(operationSubFunction,options) {
 	var name = options.suffixes[0][0];
 	// Return the filter run prefix function
 	return function(results,source,widget) {
-		// Set the input source to the incoming results
-		var inputSource = widget.wiki.makeTiddlerIterator(results.toArray());
 		// Assign the result of the subfunction to the variable
 		var variables = {};
-		variables[name] = operationSubFunction(inputSource,widget)[0] || "";
+		variables[name] = operationSubFunction(source,widget)[0] || "";
 		// Clear the results
 		results.clear();
 		// Return the variables

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

@@ -1,12 +0,0 @@
-title: LetFilterRunPrefix/All
-description: Usage of "all[]" operator within "let" filter run prefix
-type: text/vnd.tiddlywiki-multiple
-tags: [[$:/tags/wiki-test-spec]]
-
-title: Output
-
-<$text text={{{ [[colossus]] :let:another[all[]] [<another>] +[join[-]] }}}/>
-+
-title: ExpectedResult
-
-<p>colossus</p>

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

@@ -0,0 +1,12 @@
+title: LetFilterRunPrefix/UseInput
+description: Using the input of "let" filter run prefix
+type: text/vnd.tiddlywiki-multiple
+tags: [[$:/tags/wiki-test-spec]]
+
+title: Output
+
+<$text text={{{ [[colossus]] :let:another[addprefix[something]] [<another>] +[join[-]] }}}/>
++
+title: ExpectedResult
+
+<p>colossus</p>

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

@@ -20,4 +20,4 @@ type: text/vnd.tiddlywiki
 
 The `:let` filter run prefix assigns the first result of a filter run to a variable that is made available to the remaining [[filter runs|Filter Run]] in the [[filter expression|Filter Expression]]. If the filter run does not return any results then the variable is set to an empty string.
 
-Within the filter run the [[all Operator]] with an empty parameter retrieves all the titles from the previous filter runs, instead of the usual behaviour of retieving all the titles that were passed to the filter expression.
+The output of the `:let` filter run prefix is an empty title list.