kmx.io/prism.js

diff --git a/components/prism-core.js b/components/prism-core.js
index 8b8343b..29a7952 100644
--- a/components/prism-core.js
+++ b/components/prism-core.js
@@ -824,6 +824,25 @@ Token.stringify = function stringify(o, language) {
 };
 
 /**
+ * @param {RegExp} pattern
+ * @param {number} pos
+ * @param {string} text
+ * @param {boolean} lookbehind
+ * @returns {RegExpExecArray | null}
+ */
+function matchPattern(pattern, pos, text, lookbehind) {
+	pattern.lastIndex = pos;
+	var match = pattern.exec(text);
+	if (match && lookbehind && match[1]) {
+		// change the match to remove the text matched by the Prism lookbehind group
+		var lookbehindLength = match[1].length;
+		match.index += lookbehindLength;
+		match[0] = match[0].slice(lookbehindLength);
+	}
+	return match;
+}
+
+/**
  * @param {string} text
  * @param {LinkedList<string | Token>} tokenList
  * @param {any} grammar
@@ -855,7 +874,6 @@ function matchGrammar(text, tokenList, grammar, startNode, startPos, rematch) {
 				inside = patternObj.inside,
 				lookbehind = !!patternObj.lookbehind,
 				greedy = !!patternObj.greedy,
-				lookbehindLength = 0,
 				alias = patternObj.alias;
 
 			if (greedy && !patternObj.pattern.global) {
@@ -889,15 +907,15 @@ function matchGrammar(text, tokenList, grammar, startNode, startPos, rematch) {
 				}
 
 				var removeCount = 1; // this is the to parameter of removeBetween
+				var match;
 
 				if (greedy) {
-					pattern.lastIndex = pos;
-					var match = pattern.exec(text);
+					match = matchPattern(pattern, pos, text, lookbehind);
 					if (!match) {
 						break;
 					}
 
-					var from = match.index + (lookbehind && match[1] ? match[1].length : 0);
+					var from = match.index;
 					var to = match.index + match[0].length;
 					var p = pos;
 
@@ -931,24 +949,16 @@ function matchGrammar(text, tokenList, grammar, startNode, startPos, rematch) {
 					str = text.slice(pos, p);
 					match.index -= pos;
 				} else {
-					pattern.lastIndex = 0;
-
-					var match = pattern.exec(str);
-				}
-
-				if (!match) {
-					continue;
-				}
-
-				if (lookbehind) {
-					lookbehindLength = match[1] ? match[1].length : 0;
+					match = matchPattern(pattern, 0, str, lookbehind);
+					if (!match) {
+						continue;
+					}
 				}
 
-				var from = match.index + lookbehindLength,
-					matchStr = match[0].slice(lookbehindLength),
-					to = from + matchStr.length,
+				var from = match.index,
+					matchStr = match[0],
 					before = str.slice(0, from),
-					after = str.slice(to);
+					after = str.slice(from + matchStr.length);
 
 				var reach = pos + str.length;
 				if (rematch && reach > rematch.reach) {
diff --git a/components/prism-core.min.js b/components/prism-core.min.js
index 1589f00..89173b8 100644
--- a/components/prism-core.min.js
+++ b/components/prism-core.min.js
@@ -1 +1 @@
-var _self="undefined"!=typeof window?window:"undefined"!=typeof WorkerGlobalScope&&self instanceof WorkerGlobalScope?self:{},Prism=function(u){var c=/\blang(?:uage)?-([\w-]+)\b/i,n=0,M={manual:u.Prism&&u.Prism.manual,disableWorkerMessageHandler:u.Prism&&u.Prism.disableWorkerMessageHandler,util:{encode:function e(n){return n instanceof W?new W(n.type,e(n.content),n.alias):Array.isArray(n)?n.map(e):n.replace(/&/g,"&amp;").replace(/</g,"&lt;").replace(/\u00a0/g," ")},type:function(e){return Object.prototype.toString.call(e).slice(8,-1)},objId:function(e){return e.__id||Object.defineProperty(e,"__id",{value:++n}),e.__id},clone:function t(e,r){var a,n;switch(r=r||{},M.util.type(e)){case"Object":if(n=M.util.objId(e),r[n])return r[n];for(var i in a={},r[n]=a,e)e.hasOwnProperty(i)&&(a[i]=t(e[i],r));return a;case"Array":return n=M.util.objId(e),r[n]?r[n]:(a=[],r[n]=a,e.forEach(function(e,n){a[n]=t(e,r)}),a);default:return e}},getLanguage:function(e){for(;e&&!c.test(e.className);)e=e.parentElement;return e?(e.className.match(c)||[,"none"])[1].toLowerCase():"none"},currentScript:function(){if("undefined"==typeof document)return null;if("currentScript"in document)return document.currentScript;try{throw new Error}catch(e){var n=(/at [^(\r\n]*\((.*):.+:.+\)$/i.exec(e.stack)||[])[1];if(n){var t=document.getElementsByTagName("script");for(var r in t)if(t[r].src==n)return t[r]}return null}},isActive:function(e,n,t){for(var r="no-"+n;e;){var a=e.classList;if(a.contains(n))return!0;if(a.contains(r))return!1;e=e.parentElement}return!!t}},languages:{extend:function(e,n){var t=M.util.clone(M.languages[e]);for(var r in n)t[r]=n[r];return t},insertBefore:function(t,e,n,r){var a=(r=r||M.languages)[t],i={};for(var l in a)if(a.hasOwnProperty(l)){if(l==e)for(var o in n)n.hasOwnProperty(o)&&(i[o]=n[o]);n.hasOwnProperty(l)||(i[l]=a[l])}var s=r[t];return r[t]=i,M.languages.DFS(M.languages,function(e,n){n===s&&e!=t&&(this[e]=i)}),i},DFS:function e(n,t,r,a){a=a||{};var i=M.util.objId;for(var l in n)if(n.hasOwnProperty(l)){t.call(n,l,n[l],r||l);var o=n[l],s=M.util.type(o);"Object"!==s||a[i(o)]?"Array"!==s||a[i(o)]||(a[i(o)]=!0,e(o,t,l,a)):(a[i(o)]=!0,e(o,t,null,a))}}},plugins:{},highlightAll:function(e,n){M.highlightAllUnder(document,e,n)},highlightAllUnder:function(e,n,t){var r={callback:t,container:e,selector:'code[class*="language-"], [class*="language-"] code, code[class*="lang-"], [class*="lang-"] code'};M.hooks.run("before-highlightall",r),r.elements=Array.prototype.slice.apply(r.container.querySelectorAll(r.selector)),M.hooks.run("before-all-elements-highlight",r);for(var a,i=0;a=r.elements[i++];)M.highlightElement(a,!0===n,r.callback)},highlightElement:function(e,n,t){var r=M.util.getLanguage(e),a=M.languages[r];e.className=e.className.replace(c,"").replace(/\s+/g," ")+" language-"+r;var i=e.parentElement;i&&"pre"===i.nodeName.toLowerCase()&&(i.className=i.className.replace(c,"").replace(/\s+/g," ")+" language-"+r);var l={element:e,language:r,grammar:a,code:e.textContent};function o(e){l.highlightedCode=e,M.hooks.run("before-insert",l),l.element.innerHTML=l.highlightedCode,M.hooks.run("after-highlight",l),M.hooks.run("complete",l),t&&t.call(l.element)}if(M.hooks.run("before-sanity-check",l),!l.code)return M.hooks.run("complete",l),void(t&&t.call(l.element));if(M.hooks.run("before-highlight",l),l.grammar)if(n&&u.Worker){var s=new Worker(M.filename);s.onmessage=function(e){o(e.data)},s.postMessage(JSON.stringify({language:l.language,code:l.code,immediateClose:!0}))}else o(M.highlight(l.code,l.grammar,l.language));else o(M.util.encode(l.code))},highlight:function(e,n,t){var r={code:e,grammar:n,language:t};return M.hooks.run("before-tokenize",r),r.tokens=M.tokenize(r.code,r.grammar),M.hooks.run("after-tokenize",r),W.stringify(M.util.encode(r.tokens),r.language)},tokenize:function(e,n){var t=n.rest;if(t){for(var r in t)n[r]=t[r];delete n.rest}var a=new i;return I(a,a.head,e),function e(n,t,r,a,i,l){for(var o in r)if(r.hasOwnProperty(o)&&r[o]){var s=r[o];s=Array.isArray(s)?s:[s];for(var u=0;u<s.length;++u){if(l&&l.cause==o+","+u)return;var c=s[u],g=c.inside,f=!!c.lookbehind,h=!!c.greedy,d=0,v=c.alias;if(h&&!c.pattern.global){var p=c.pattern.toString().match(/[imsuy]*$/)[0];c.pattern=RegExp(c.pattern.source,p+"g")}for(var m=c.pattern||c,y=a.next,k=i;y!==t.tail&&!(l&&k>=l.reach);k+=y.value.length,y=y.next){var b=y.value;if(t.length>n.length)return;if(!(b instanceof W)){var x=1;if(h){m.lastIndex=k;var w=m.exec(n);if(!w)break;var A=w.index+(f&&w[1]?w[1].length:0),P=w.index+w[0].length,S=k;for(S+=y.value.length;S<=A;)y=y.next,S+=y.value.length;if(S-=y.value.length,k=S,y.value instanceof W)continue;for(var E=y;E!==t.tail&&(S<P||"string"==typeof E.value);E=E.next)x++,S+=E.value.length;x--,b=n.slice(k,S),w.index-=k}else{m.lastIndex=0;var w=m.exec(b)}if(w){f&&(d=w[1]?w[1].length:0);var A=w.index+d,O=w[0].slice(d),P=A+O.length,L=b.slice(0,A),N=b.slice(P),j=k+b.length;l&&j>l.reach&&(l.reach=j);var C=y.prev;L&&(C=I(t,C,L),k+=L.length),z(t,C,x);var _=new W(o,g?M.tokenize(O,g):O,v,O);y=I(t,C,_),N&&I(t,y,N),1<x&&e(n,t,r,y.prev,k,{cause:o+","+u,reach:j})}}}}}}(e,a,n,a.head,0),function(e){var n=[],t=e.head.next;for(;t!==e.tail;)n.push(t.value),t=t.next;return n}(a)},hooks:{all:{},add:function(e,n){var t=M.hooks.all;t[e]=t[e]||[],t[e].push(n)},run:function(e,n){var t=M.hooks.all[e];if(t&&t.length)for(var r,a=0;r=t[a++];)r(n)}},Token:W};function W(e,n,t,r){this.type=e,this.content=n,this.alias=t,this.length=0|(r||"").length}function i(){var e={value:null,prev:null,next:null},n={value:null,prev:e,next:null};e.next=n,this.head=e,this.tail=n,this.length=0}function I(e,n,t){var r=n.next,a={value:t,prev:n,next:r};return n.next=a,r.prev=a,e.length++,a}function z(e,n,t){for(var r=n.next,a=0;a<t&&r!==e.tail;a++)r=r.next;(n.next=r).prev=n,e.length-=a}if(u.Prism=M,W.stringify=function n(e,t){if("string"==typeof e)return e;if(Array.isArray(e)){var r="";return e.forEach(function(e){r+=n(e,t)}),r}var a={type:e.type,content:n(e.content,t),tag:"span",classes:["token",e.type],attributes:{},language:t},i=e.alias;i&&(Array.isArray(i)?Array.prototype.push.apply(a.classes,i):a.classes.push(i)),M.hooks.run("wrap",a);var l="";for(var o in a.attributes)l+=" "+o+'="'+(a.attributes[o]||"").replace(/"/g,"&quot;")+'"';return"<"+a.tag+' class="'+a.classes.join(" ")+'"'+l+">"+a.content+"</"+a.tag+">"},!u.document)return u.addEventListener&&(M.disableWorkerMessageHandler||u.addEventListener("message",function(e){var n=JSON.parse(e.data),t=n.language,r=n.code,a=n.immediateClose;u.postMessage(M.highlight(r,M.languages[t],t)),a&&u.close()},!1)),M;var e=M.util.currentScript();function t(){M.manual||M.highlightAll()}if(e&&(M.filename=e.src,e.hasAttribute("data-manual")&&(M.manual=!0)),!M.manual){var r=document.readyState;"loading"===r||"interactive"===r&&e&&e.defer?document.addEventListener("DOMContentLoaded",t):window.requestAnimationFrame?window.requestAnimationFrame(t):window.setTimeout(t,16)}return M}(_self);"undefined"!=typeof module&&module.exports&&(module.exports=Prism),"undefined"!=typeof global&&(global.Prism=Prism);
\ No newline at end of file
+var _self="undefined"!=typeof window?window:"undefined"!=typeof WorkerGlobalScope&&self instanceof WorkerGlobalScope?self:{},Prism=function(u){var c=/\blang(?:uage)?-([\w-]+)\b/i,n=0,_={manual:u.Prism&&u.Prism.manual,disableWorkerMessageHandler:u.Prism&&u.Prism.disableWorkerMessageHandler,util:{encode:function e(n){return n instanceof M?new M(n.type,e(n.content),n.alias):Array.isArray(n)?n.map(e):n.replace(/&/g,"&amp;").replace(/</g,"&lt;").replace(/\u00a0/g," ")},type:function(e){return Object.prototype.toString.call(e).slice(8,-1)},objId:function(e){return e.__id||Object.defineProperty(e,"__id",{value:++n}),e.__id},clone:function t(e,r){var a,n;switch(r=r||{},_.util.type(e)){case"Object":if(n=_.util.objId(e),r[n])return r[n];for(var i in a={},r[n]=a,e)e.hasOwnProperty(i)&&(a[i]=t(e[i],r));return a;case"Array":return n=_.util.objId(e),r[n]?r[n]:(a=[],r[n]=a,e.forEach(function(e,n){a[n]=t(e,r)}),a);default:return e}},getLanguage:function(e){for(;e&&!c.test(e.className);)e=e.parentElement;return e?(e.className.match(c)||[,"none"])[1].toLowerCase():"none"},currentScript:function(){if("undefined"==typeof document)return null;if("currentScript"in document)return document.currentScript;try{throw new Error}catch(e){var n=(/at [^(\r\n]*\((.*):.+:.+\)$/i.exec(e.stack)||[])[1];if(n){var t=document.getElementsByTagName("script");for(var r in t)if(t[r].src==n)return t[r]}return null}},isActive:function(e,n,t){for(var r="no-"+n;e;){var a=e.classList;if(a.contains(n))return!0;if(a.contains(r))return!1;e=e.parentElement}return!!t}},languages:{extend:function(e,n){var t=_.util.clone(_.languages[e]);for(var r in n)t[r]=n[r];return t},insertBefore:function(t,e,n,r){var a=(r=r||_.languages)[t],i={};for(var l in a)if(a.hasOwnProperty(l)){if(l==e)for(var o in n)n.hasOwnProperty(o)&&(i[o]=n[o]);n.hasOwnProperty(l)||(i[l]=a[l])}var s=r[t];return r[t]=i,_.languages.DFS(_.languages,function(e,n){n===s&&e!=t&&(this[e]=i)}),i},DFS:function e(n,t,r,a){a=a||{};var i=_.util.objId;for(var l in n)if(n.hasOwnProperty(l)){t.call(n,l,n[l],r||l);var o=n[l],s=_.util.type(o);"Object"!==s||a[i(o)]?"Array"!==s||a[i(o)]||(a[i(o)]=!0,e(o,t,l,a)):(a[i(o)]=!0,e(o,t,null,a))}}},plugins:{},highlightAll:function(e,n){_.highlightAllUnder(document,e,n)},highlightAllUnder:function(e,n,t){var r={callback:t,container:e,selector:'code[class*="language-"], [class*="language-"] code, code[class*="lang-"], [class*="lang-"] code'};_.hooks.run("before-highlightall",r),r.elements=Array.prototype.slice.apply(r.container.querySelectorAll(r.selector)),_.hooks.run("before-all-elements-highlight",r);for(var a,i=0;a=r.elements[i++];)_.highlightElement(a,!0===n,r.callback)},highlightElement:function(e,n,t){var r=_.util.getLanguage(e),a=_.languages[r];e.className=e.className.replace(c,"").replace(/\s+/g," ")+" language-"+r;var i=e.parentElement;i&&"pre"===i.nodeName.toLowerCase()&&(i.className=i.className.replace(c,"").replace(/\s+/g," ")+" language-"+r);var l={element:e,language:r,grammar:a,code:e.textContent};function o(e){l.highlightedCode=e,_.hooks.run("before-insert",l),l.element.innerHTML=l.highlightedCode,_.hooks.run("after-highlight",l),_.hooks.run("complete",l),t&&t.call(l.element)}if(_.hooks.run("before-sanity-check",l),!l.code)return _.hooks.run("complete",l),void(t&&t.call(l.element));if(_.hooks.run("before-highlight",l),l.grammar)if(n&&u.Worker){var s=new Worker(_.filename);s.onmessage=function(e){o(e.data)},s.postMessage(JSON.stringify({language:l.language,code:l.code,immediateClose:!0}))}else o(_.highlight(l.code,l.grammar,l.language));else o(_.util.encode(l.code))},highlight:function(e,n,t){var r={code:e,grammar:n,language:t};return _.hooks.run("before-tokenize",r),r.tokens=_.tokenize(r.code,r.grammar),_.hooks.run("after-tokenize",r),M.stringify(_.util.encode(r.tokens),r.language)},tokenize:function(e,n){var t=n.rest;if(t){for(var r in t)n[r]=t[r];delete n.rest}var a=new i;return z(a,a.head,e),function e(n,t,r,a,i,l){for(var o in r)if(r.hasOwnProperty(o)&&r[o]){var s=r[o];s=Array.isArray(s)?s:[s];for(var u=0;u<s.length;++u){if(l&&l.cause==o+","+u)return;var c=s[u],g=c.inside,f=!!c.lookbehind,h=!!c.greedy,d=c.alias;if(h&&!c.pattern.global){var v=c.pattern.toString().match(/[imsuy]*$/)[0];c.pattern=RegExp(c.pattern.source,v+"g")}for(var p=c.pattern||c,m=a.next,y=i;m!==t.tail&&!(l&&y>=l.reach);y+=m.value.length,m=m.next){var k=m.value;if(t.length>n.length)return;if(!(k instanceof M)){var b,x=1;if(h){if(!(b=W(p,y,n,f)))break;var w=b.index,A=b.index+b[0].length,P=y;for(P+=m.value.length;P<=w;)m=m.next,P+=m.value.length;if(P-=m.value.length,y=P,m.value instanceof M)continue;for(var S=m;S!==t.tail&&(P<A||"string"==typeof S.value);S=S.next)x++,P+=S.value.length;x--,k=n.slice(y,P),b.index-=y}else if(!(b=W(p,0,k,f)))continue;var w=b.index,E=b[0],O=k.slice(0,w),L=k.slice(w+E.length),N=y+k.length;l&&N>l.reach&&(l.reach=N);var j=m.prev;O&&(j=z(t,j,O),y+=O.length),I(t,j,x);var C=new M(o,g?_.tokenize(E,g):E,d,E);m=z(t,j,C),L&&z(t,m,L),1<x&&e(n,t,r,m.prev,y,{cause:o+","+u,reach:N})}}}}}(e,a,n,a.head,0),function(e){var n=[],t=e.head.next;for(;t!==e.tail;)n.push(t.value),t=t.next;return n}(a)},hooks:{all:{},add:function(e,n){var t=_.hooks.all;t[e]=t[e]||[],t[e].push(n)},run:function(e,n){var t=_.hooks.all[e];if(t&&t.length)for(var r,a=0;r=t[a++];)r(n)}},Token:M};function M(e,n,t,r){this.type=e,this.content=n,this.alias=t,this.length=0|(r||"").length}function W(e,n,t,r){e.lastIndex=n;var a=e.exec(t);if(a&&r&&a[1]){var i=a[1].length;a.index+=i,a[0]=a[0].slice(i)}return a}function i(){var e={value:null,prev:null,next:null},n={value:null,prev:e,next:null};e.next=n,this.head=e,this.tail=n,this.length=0}function z(e,n,t){var r=n.next,a={value:t,prev:n,next:r};return n.next=a,r.prev=a,e.length++,a}function I(e,n,t){for(var r=n.next,a=0;a<t&&r!==e.tail;a++)r=r.next;(n.next=r).prev=n,e.length-=a}if(u.Prism=_,M.stringify=function n(e,t){if("string"==typeof e)return e;if(Array.isArray(e)){var r="";return e.forEach(function(e){r+=n(e,t)}),r}var a={type:e.type,content:n(e.content,t),tag:"span",classes:["token",e.type],attributes:{},language:t},i=e.alias;i&&(Array.isArray(i)?Array.prototype.push.apply(a.classes,i):a.classes.push(i)),_.hooks.run("wrap",a);var l="";for(var o in a.attributes)l+=" "+o+'="'+(a.attributes[o]||"").replace(/"/g,"&quot;")+'"';return"<"+a.tag+' class="'+a.classes.join(" ")+'"'+l+">"+a.content+"</"+a.tag+">"},!u.document)return u.addEventListener&&(_.disableWorkerMessageHandler||u.addEventListener("message",function(e){var n=JSON.parse(e.data),t=n.language,r=n.code,a=n.immediateClose;u.postMessage(_.highlight(r,_.languages[t],t)),a&&u.close()},!1)),_;var e=_.util.currentScript();function t(){_.manual||_.highlightAll()}if(e&&(_.filename=e.src,e.hasAttribute("data-manual")&&(_.manual=!0)),!_.manual){var r=document.readyState;"loading"===r||"interactive"===r&&e&&e.defer?document.addEventListener("DOMContentLoaded",t):window.requestAnimationFrame?window.requestAnimationFrame(t):window.setTimeout(t,16)}return _}(_self);"undefined"!=typeof module&&module.exports&&(module.exports=Prism),"undefined"!=typeof global&&(global.Prism=Prism);
\ No newline at end of file
diff --git a/docs/global.html b/docs/global.html
index 3801628..4838a92 100644
--- a/docs/global.html
+++ b/docs/global.html
@@ -143,7 +143,7 @@
     
     <dt class="tag-source">Source:</dt>
     <dd class="tag-source"><ul class="dummy"><li>
-        <a href="prism-core.js.html">prism-core.js</a>, <a href="prism-core.js.html#line1161">line 1161</a>
+        <a href="prism-core.js.html">prism-core.js</a>, <a href="prism-core.js.html#line1171">line 1171</a>
     </li></ul></dd>
     
 
@@ -274,7 +274,7 @@
     
     <dt class="tag-source">Source:</dt>
     <dd class="tag-source"><ul class="dummy"><li>
-        <a href="prism-core.js.html">prism-core.js</a>, <a href="prism-core.js.html#line1140">line 1140</a>
+        <a href="prism-core.js.html">prism-core.js</a>, <a href="prism-core.js.html#line1150">line 1150</a>
     </li></ul></dd>
     
 
@@ -559,7 +559,7 @@ each another.</p></td>
     
     <dt class="tag-source">Source:</dt>
     <dd class="tag-source"><ul class="dummy"><li>
-        <a href="prism-core.js.html">prism-core.js</a>, <a href="prism-core.js.html#line1169">line 1169</a>
+        <a href="prism-core.js.html">prism-core.js</a>, <a href="prism-core.js.html#line1179">line 1179</a>
     </li></ul></dd>
     
 
@@ -713,7 +713,7 @@ each another.</p></td>
     
     <dt class="tag-source">Source:</dt>
     <dd class="tag-source"><ul class="dummy"><li>
-        <a href="prism-core.js.html">prism-core.js</a>, <a href="prism-core.js.html#line1179">line 1179</a>
+        <a href="prism-core.js.html">prism-core.js</a>, <a href="prism-core.js.html#line1189">line 1189</a>
     </li></ul></dd>
     
 
diff --git a/docs/prism-core.js.html b/docs/prism-core.js.html
index f8a5edc..ed5112a 100644
--- a/docs/prism-core.js.html
+++ b/docs/prism-core.js.html
@@ -877,6 +877,25 @@ Token.stringify = function stringify(o, language) {
 };
 
 /**
+ * @param {RegExp} pattern
+ * @param {number} pos
+ * @param {string} text
+ * @param {boolean} lookbehind
+ * @returns {RegExpExecArray | null}
+ */
+function matchPattern(pattern, pos, text, lookbehind) {
+	pattern.lastIndex = pos;
+	var match = pattern.exec(text);
+	if (match &amp;&amp; lookbehind &amp;&amp; match[1]) {
+		// change the match to remove the text matched by the Prism lookbehind group
+		var lookbehindLength = match[1].length;
+		match.index += lookbehindLength;
+		match[0] = match[0].slice(lookbehindLength);
+	}
+	return match;
+}
+
+/**
  * @param {string} text
  * @param {LinkedList&lt;string | Token>} tokenList
  * @param {any} grammar
@@ -908,7 +927,6 @@ function matchGrammar(text, tokenList, grammar, startNode, startPos, rematch) {
 				inside = patternObj.inside,
 				lookbehind = !!patternObj.lookbehind,
 				greedy = !!patternObj.greedy,
-				lookbehindLength = 0,
 				alias = patternObj.alias;
 
 			if (greedy &amp;&amp; !patternObj.pattern.global) {
@@ -942,15 +960,15 @@ function matchGrammar(text, tokenList, grammar, startNode, startPos, rematch) {
 				}
 
 				var removeCount = 1; // this is the to parameter of removeBetween
+				var match;
 
 				if (greedy) {
-					pattern.lastIndex = pos;
-					var match = pattern.exec(text);
+					match = matchPattern(pattern, pos, text, lookbehind);
 					if (!match) {
 						break;
 					}
 
-					var from = match.index + (lookbehind &amp;&amp; match[1] ? match[1].length : 0);
+					var from = match.index;
 					var to = match.index + match[0].length;
 					var p = pos;
 
@@ -984,24 +1002,16 @@ function matchGrammar(text, tokenList, grammar, startNode, startPos, rematch) {
 					str = text.slice(pos, p);
 					match.index -= pos;
 				} else {
-					pattern.lastIndex = 0;
-
-					var match = pattern.exec(str);
-				}
-
-				if (!match) {
-					continue;
-				}
-
-				if (lookbehind) {
-					lookbehindLength = match[1] ? match[1].length : 0;
+					match = matchPattern(pattern, 0, str, lookbehind);
+					if (!match) {
+						continue;
+					}
 				}
 
-				var from = match.index + lookbehindLength,
-					matchStr = match[0].slice(lookbehindLength),
-					to = from + matchStr.length,
+				var from = match.index,
+					matchStr = match[0],
 					before = str.slice(0, from),
-					after = str.slice(to);
+					after = str.slice(from + matchStr.length);
 
 				var reach = pos + str.length;
 				if (rematch &amp;&amp; reach > rematch.reach) {
diff --git a/prism.js b/prism.js
index 02af74b..cab8797 100644
--- a/prism.js
+++ b/prism.js
@@ -829,6 +829,25 @@ Token.stringify = function stringify(o, language) {
 };
 
 /**
+ * @param {RegExp} pattern
+ * @param {number} pos
+ * @param {string} text
+ * @param {boolean} lookbehind
+ * @returns {RegExpExecArray | null}
+ */
+function matchPattern(pattern, pos, text, lookbehind) {
+	pattern.lastIndex = pos;
+	var match = pattern.exec(text);
+	if (match && lookbehind && match[1]) {
+		// change the match to remove the text matched by the Prism lookbehind group
+		var lookbehindLength = match[1].length;
+		match.index += lookbehindLength;
+		match[0] = match[0].slice(lookbehindLength);
+	}
+	return match;
+}
+
+/**
  * @param {string} text
  * @param {LinkedList<string | Token>} tokenList
  * @param {any} grammar
@@ -860,7 +879,6 @@ function matchGrammar(text, tokenList, grammar, startNode, startPos, rematch) {
 				inside = patternObj.inside,
 				lookbehind = !!patternObj.lookbehind,
 				greedy = !!patternObj.greedy,
-				lookbehindLength = 0,
 				alias = patternObj.alias;
 
 			if (greedy && !patternObj.pattern.global) {
@@ -894,15 +912,15 @@ function matchGrammar(text, tokenList, grammar, startNode, startPos, rematch) {
 				}
 
 				var removeCount = 1; // this is the to parameter of removeBetween
+				var match;
 
 				if (greedy) {
-					pattern.lastIndex = pos;
-					var match = pattern.exec(text);
+					match = matchPattern(pattern, pos, text, lookbehind);
 					if (!match) {
 						break;
 					}
 
-					var from = match.index + (lookbehind && match[1] ? match[1].length : 0);
+					var from = match.index;
 					var to = match.index + match[0].length;
 					var p = pos;
 
@@ -936,24 +954,16 @@ function matchGrammar(text, tokenList, grammar, startNode, startPos, rematch) {
 					str = text.slice(pos, p);
 					match.index -= pos;
 				} else {
-					pattern.lastIndex = 0;
-
-					var match = pattern.exec(str);
-				}
-
-				if (!match) {
-					continue;
-				}
-
-				if (lookbehind) {
-					lookbehindLength = match[1] ? match[1].length : 0;
+					match = matchPattern(pattern, 0, str, lookbehind);
+					if (!match) {
+						continue;
+					}
 				}
 
-				var from = match.index + lookbehindLength,
-					matchStr = match[0].slice(lookbehindLength),
-					to = from + matchStr.length,
+				var from = match.index,
+					matchStr = match[0],
 					before = str.slice(0, from),
-					after = str.slice(to);
+					after = str.slice(from + matchStr.length);
 
 				var reach = pos + str.length;
 				if (rematch && reach > rematch.reach) {