Implement explicit external links

core/modules/parsers/wikiparser/rules/prettyextlink.js

@@ -0,0 +1,112 @@
+/*\
+title: $:/core/modules/parsers/wikiparser/rules/prettyextlink.js
+type: application/javascript
+module-type: wikirule
+
+Wiki text inline rule for external links. For example:
+
+```
+[ext[http://tiddlywiki.com/fractalveg.jpg]]
+[ext[Tooltip|http://tiddlywiki.com/fractalveg.jpg]]
+```
+
+\*/
+(function(){
+
+/*jslint node: true, browser: true */
+/*global $tw: false */
+"use strict";
+
+exports.name = "prettyextlink";
+exports.types = {inline: true};
+
+exports.init = function(parser) {
+	this.parser = parser;
+};
+
+exports.findNextMatch = function(startPos) {
+	// Find the next tag
+	this.nextLink = this.findNextLink(this.parser.source,startPos);
+	return this.nextLink ? this.nextLink.start : undefined;
+};
+
+exports.parse = function() {
+	// Move past the match
+	this.parser.pos = this.nextLink.end;
+	return [this.nextLink];
+};
+
+/*
+Find the next link from the current position
+*/
+exports.findNextLink = function(source,pos) {
+	// A regexp for finding candidate links
+	var reLookahead = /(\[ext\[)/g;
+	// Find the next candidate
+	reLookahead.lastIndex = pos;
+	var match = reLookahead.exec(source);
+	while(match) {
+		// Try to parse the candidate as a link
+		var link = this.parseLink(source,match.index);
+		// Return success
+		if(link) {
+			return link;
+		}
+		// Look for the next match
+		reLookahead.lastIndex = match.index + 1;
+		match = reLookahead.exec(source);
+	}
+	// Failed
+	return null;
+};
+
+/*
+Look for an link at the specified position. Returns null if not found, otherwise returns {type: "element", tag: "a", attributes: [], isSelfClosing:, start:, end:,}
+*/
+exports.parseLink = function(source,pos) {
+	var token,
+		textNode = {
+			type: "text"
+		},
+		node = {
+			type: "element",
+			tag: "a",
+			start: pos,
+			attributes: {},
+			children: [textNode]
+		};
+	// Skip whitespace
+	pos = $tw.utils.skipWhiteSpace(source,pos);
+	// Look for the `[ext[`
+	token = $tw.utils.parseTokenString(source,pos,"[ext[");
+	if(!token) {
+		return null;
+	}
+	pos = token.end;
+	// Look ahead for the terminating `]]`
+	var closePos = source.indexOf("]]",pos);
+	if(closePos === -1) {
+		return null;
+	}
+	// Look for a `|` separating the tooltip
+	var splitPos = source.indexOf("|",pos);
+	if(splitPos === -1 || splitPos > closePos) {
+		splitPos = null;
+	}
+	// Pull out the tooltip and URL
+	var tooltip, URL;
+	if(splitPos) {
+		URL = source.substring(splitPos + 1,closePos).trim();
+		textNode.text = source.substring(pos,splitPos).trim();
+	} else {
+		URL = source.substring(pos,closePos).trim();
+		textNode.text = URL;
+	}
+	node.attributes.href = {type: "string", value: URL};
+	node.attributes.target = {type: "string", value: "_blank"};
+	// Update the end position
+	node.end = closePos + 2;
+	return node;
+};
+
+})();

editions/tw5.com/tiddlers/Release 5.0.11beta.tid

@@ -21,6 +21,7 @@ See [[Notes for upgrading to 5.0.11-beta]] for more details of these changes:
 * Many performance optimisations, particularly for filter operations
 * Added support for PermaLinks
 * Added support for WikiLinks in Markdown via `[link text](#TiddlerTitle)`
+* Added support for explicit external [[Linking in WikiText]] (eg `[ext[tooltip|url]]`)
 * [[Replaced|https://github.com/Jermolene/TiddlyWiki5/issues/580]] hamburger menu icon with double chevron icon
 * [[Enhance|https://github.com/Jermolene/TiddlyWiki5/commit/552657fc584dbb36754d3fcabca2cdef7e916ec9]] plain text parsing to use the CodeBlockWidget, and hence use syntax highlighting if the plugin is installed. This gives us syntax highlighting for JavaScript shadow tiddlers, amongst other things
 * Improvements to Chinese, Japanese and French translations

editions/tw5.com/tiddlers/roadmap/RoadMap.tid

@@ -23,7 +23,7 @@ The following additional features are planned or under consideration for impleme
 ** Tiddler object format (to provide true polymorphism of field values)
 * Perfecting WikiText
 ** Global macros
-** ~~`[img[url]]` for remote image embedding~~, and `[ext[url]]` for explicit external links
+** ~~`[img[url]]` for remote image embedding, and `[ext[url]]` for explicit external links~~
 ** Further ~WikiText features
 * Productivity features
 ** Import wizard allowing individual tiddlers to be selected for import

editions/tw5.com/tiddlers/wikitext/Linking in WikiText.tid

@@ -1,15 +1,42 @@
 created: 20131205155230596
-modified: 20131205155813974
+modified: 20130506185813974
 tags: wikitext
 title: Linking in WikiText
 type: text/vnd.tiddlywiki
 
 A key capability of WikiText is the ability to make links to other tiddlers or to external websites. There are several ways of doing this:
 
-* To link to a tiddler by title: `[[Tiddler Title]]`
-* To link to a tiddler and specify the text of the link: `[[Displayed Link Title|Tiddler Title]]`
-* For tiddler titles that match the CamelCase rules, just typing the title will automatically create a link
-* To link to an external website, type the full URL of the site: `http://tiddlywiki.com/` or `[[TW5|http://tiddlywiki.com/]]`
+Link to a tiddler by title:
+
+```
+[[Tiddler Title]]
+```
+
+To link to a tiddler and specify the text of the link:
+
+```
+[[Displayed Link Title|Tiddler Title]]
+```
+
+For tiddler titles that match the CamelCase rules, just typing the title will automatically create a link.
+
+To link to an external website, type the full URL of the site:
+
+```
+http://tiddlywiki.com/
+
+[[TW5|http://tiddlywiki.com/]]
+```
+
+For this syntax to work, the URL has to be recognisable as an URL, including a protocol such as `http://` or `file://`. You can force an external link with the extended syntax:
+
+```
+[ext[tiddlywiki.com]]
+
+[ext[caption for link|tiddlywiki.com]]
+
+[ext[Donate|bitcoin:1aabbdd....?amount=0.001]]
+```
 
 You can suppress a link from being recognised by preceding it with `~`. For example: