From 52592a4dbcc6a4990442d8755607a12dbc6a0d26 Mon Sep 17 00:00:00 2001
From: "jeremy@jermolene.com" <jeremy@jermolene.com>
Date: Wed, 23 Nov 2022 16:30:20 +0000
Subject: [PATCH] Add support for named end markers for procedures, functions
 and widgets

---
 .../parsers/wikiparser/rules/fnprocdef.js     |  2 +-
 .../tiddlers/tests/data/procedures/Nested.tid | 20 +++++++++++++++++++
 .../tiddlers/pragmas/Pragma_ _function.tid    |  4 +++-
 .../tiddlers/pragmas/Pragma_ _procedure.tid   | 18 ++++++++++++++++-
 .../tiddlers/pragmas/Pragma_ _widget.tid      |  4 +++-
 5 files changed, 44 insertions(+), 4 deletions(-)
 create mode 100644 editions/test/tiddlers/tests/data/procedures/Nested.tid

diff --git a/core/modules/parsers/wikiparser/rules/fnprocdef.js b/core/modules/parsers/wikiparser/rules/fnprocdef.js
index 12ac33cac..5d0a8878b 100644
--- a/core/modules/parsers/wikiparser/rules/fnprocdef.js
+++ b/core/modules/parsers/wikiparser/rules/fnprocdef.js
@@ -53,7 +53,7 @@ exports.parse = function() {
 	var reEnd;
 	if(this.match[5]) {
 		// If so, the end of the body is marked with \end
-		reEnd = /(\r?\n\\end[^\S\n\r]*(?:$|\r?\n))/mg;
+		reEnd = new RegExp("(\\r?\\n\\\\end[^\\S\\n\\r]*(?:" + $tw.utils.escapeRegExp(this.match[2]) + ")?(?:$|\\r?\\n))","mg");
 	} else {
 		// Otherwise, the end of the definition is marked by the end of the line
 		reEnd = /($|\r?\n)/mg;
diff --git a/editions/test/tiddlers/tests/data/procedures/Nested.tid b/editions/test/tiddlers/tests/data/procedures/Nested.tid
new file mode 100644
index 000000000..f63c634af
--- /dev/null
+++ b/editions/test/tiddlers/tests/data/procedures/Nested.tid
@@ -0,0 +1,20 @@
+title: Procedures/Nested
+description: Nested Procedures
+type: text/vnd.tiddlywiki-multiple
+tags: [[$:/tags/wiki-test-spec]]
+
+title: Output
+
+\whitespace trim
+\procedure alpha(x)
+\procedure beta(y)
+<$text text=<<y>>/>
+\end beta
+<$transclude $variable="beta" y={{{ [<x>addprefix<x>] }}}/>
+\end alpha
+
+<<alpha "Elephant">>
++
+title: ExpectedResult
+
+<p>ElephantElephant</p>
\ No newline at end of file
diff --git a/editions/tw5.com/tiddlers/pragmas/Pragma_ _function.tid b/editions/tw5.com/tiddlers/pragmas/Pragma_ _function.tid
index 24c17d9ea..ffcd76b43 100644
--- a/editions/tw5.com/tiddlers/pragmas/Pragma_ _function.tid	
+++ b/editions/tw5.com/tiddlers/pragmas/Pragma_ _function.tid	
@@ -11,9 +11,11 @@ The usual form allows custom functions to span multiple lines:
 ```
 \function <function-name>(<param-name>[:<param-default-value>],<param-name>[:<param-default-value>]...)
 <multiple-line-definition-text>
-\end
+\end [<function-name>]
 ```
 
+Note that the `\end` marker can optionally specify the name of the function to which it relates, enabling function definitions to be nested inside procedures, macros or widget definitions.
+
 There is also a single line form for shorter functions:
 
 ```
diff --git a/editions/tw5.com/tiddlers/pragmas/Pragma_ _procedure.tid b/editions/tw5.com/tiddlers/pragmas/Pragma_ _procedure.tid
index 948a863dd..becec39f9 100644
--- a/editions/tw5.com/tiddlers/pragmas/Pragma_ _procedure.tid	
+++ b/editions/tw5.com/tiddlers/pragmas/Pragma_ _procedure.tid	
@@ -11,9 +11,11 @@ The usual form allows procedures to span multiple lines:
 ```
 \procedure <procedure-name>(<param-name>[:<param-default-value>],<param-name>[:<param-default-value>]...)
 <multiple-line-definition-text>
-\end
+\end [<procedure-name>]
 ```
 
+Note that the `\end` marker can optionally specify the name of the procedure to which it relates which allows procedure definitions to be nested.
+
 There is also a single line form for shorter procedures:
 
 ```
@@ -37,3 +39,17 @@ Alternatively, the entire definition can be presented on a single line without a
 ```
 \procedure sayhi(name:"Bugs Bunny") Hi, I'm $name$.
 ```
+
+Procedure definitions can be nested by specifying the name of the procedure in the `\end` marker. For example:
+
+<<wikitext-example-without-html src:"""\procedure special-button(caption:"Click me")
+\procedure actions()
+<$action-sendmessage $message="tm-notify" $param="HelloThere"/>
+\end actions
+<$button actions=<<actions>>>
+$caption$
+</$button>
+\end special-button
+
+<<special-button>>
+""">>
\ No newline at end of file
diff --git a/editions/tw5.com/tiddlers/pragmas/Pragma_ _widget.tid b/editions/tw5.com/tiddlers/pragmas/Pragma_ _widget.tid
index bf9c228e6..e7b505c92 100644
--- a/editions/tw5.com/tiddlers/pragmas/Pragma_ _widget.tid	
+++ b/editions/tw5.com/tiddlers/pragmas/Pragma_ _widget.tid	
@@ -11,9 +11,11 @@ The usual form allows custom widgets to span multiple lines:
 ```
 \widget <widget-name>(<param-name>[:<param-default-value>],<param-name>[:<param-default-value>]...)
 <multiple-line-definition-text>
-\end
+\end [<widget-name>]
 ```
 
+Note that the `\end` marker can optionally specify the name of the widget to which it relates which allows widget definitions to be nested.
+
 There is also a single line form for shorter widgets:
 
 ```