diff --git a/docs/assets/js/site.js b/docs/assets/js/site.js
index fd1933a..c87261b 100644
--- a/docs/assets/js/site.js
+++ b/docs/assets/js/site.js
@@ -1 +1 @@
-!function(){"use strict";function a(e){return function(e){if(Array.isArray(e)){for(var t=0,n=new Array(e.length);t<e.length;t++)n[t]=e[t];return n}}(e)||function(e){if(Symbol.iterator in Object(e)||"[object Arguments]"===Object.prototype.toString.call(e))return Array.from(e)}(e)||function(){throw new TypeError("Invalid attempt to spread non-iterable instance")}()}anchors.options.placement="left",anchors.add("h3").remove(".no-anchor");var c=document.querySelector("toc").querySelectorAll("li"),u=document.querySelector("filter-input");u.addEventListener("keyup",function(e){if(13===e.keyCode)for(var t=0;t<c.length;t++){var n=c[t];if(!n.classList.contains("display-none"))return location.replace(n.firstChild.href),e.preventDefault()}var r=function(){return!0},o=u.value.toLowerCase();o.match(/^\s*$/)||(r=function(e){return-1!==e.firstChild.innerHTML.toLowerCase().indexOf(o)});for(var i=0;i<c.length;i++){var l=c[i],s=a(l.querySelectorAll("li"));r(l)||s.some(r)?l.classList.remove("display-none"):l.classList.add("display-none")}});for(var e=document.querySelectorAll("toggle-step-sibling"),t=0;t<e.length;t++)e[t].addEventListener("click",r);function n(e,t,n){e.classList.contains(n)?(e.classList.remove(n),t.innerHTML="▾"):(e.classList.add(n),t.innerHTML="▸")}function r(){var e=this.parentNode.parentNode.parentNode.querySelectorAll("toggle-target")[0];n(e,e,"display-none")}for(var o=document.querySelectorAll("toggle-sibling"),i=0;i<o.length;i++)o[i].addEventListener("click",l);function l(){n(this.parentNode.querySelectorAll("toggle-target")[0],this.querySelectorAll("icon")[0],"display-none")}function s(e){var t=document.querySelector(e);t&&0===t.offsetHeight&&t.parentNode.parentNode.classList.contains("display-none")&&t.parentNode.parentNode.classList.remove("display-none")}window.addEventListener("hashchange",function(){s(location.hash.substring(1))}),s(location.hash.substring(1));for(var d=document.querySelectorAll("pre-open"),f=0;f<d.length;f++)d[f].addEventListener("mousedown",p,!1);function p(){s(this.hash.substring(1))}var h=document.querySelector("#split-left"),y=document.querySelector("#split-right");function g(){history.replaceState({leftTop:h.scrollTop,rightTop:y.scrollTop},document.title)}function v(e){e&&history.replaceState(e.state,document.title),history.state&&(h.scrollTop=history.state.leftTop,y.scrollTop=history.state.rightTop)}h.style.overflow="hidden",h.style.overflow="",Split(["#split-left","#split-right"],{elementStyle:function(e,t,n){return{"flex-basis":"calc("+t+"% - "+n+"px)"}},gutterStyle:function(e,t){return{"flex-basis":t+"px"}},gutterSize:20,sizes:[20,80]}),window.addEventListener("load",function(){setTimeout(function(){v(),g(),h.addEventListener("scroll",g),y.addEventListener("scroll",g)},1)}),window.addEventListener("popstate",v)}();
+!function(){"use strict";function a(e){return function(e){if(Array.isArray(e)){for(var t=0,n=new Array(e.length);t<e.length;t++)n[t]=e[t];return n}}(e)||function(e){if(Symbol.iterator in Object(e)||"[object Arguments]"===Object.prototype.toString.call(e))return Array.from(e)}(e)||function(){throw new TypeError("Invalid attempt to spread non-iterable instance")}()}anchors.options.placement="left",anchors.add("h3").remove(".no-anchor");var c=document.querySelector("#toc").querySelectorAll("li"),d=document.querySelector("#filter-input");d.addEventListener("keyup",function(e){if(13===e.keyCode)for(var t=0;t<c.length;t++){var n=c[t];if(!n.classList.contains("display-none"))return location.replace(n.firstChild.href),e.preventDefault()}var r=function(){return!0},o=d.value.toLowerCase();o.match(/^\s*$/)||(r=function(e){return-1!==e.firstChild.innerHTML.toLowerCase().indexOf(o)});for(var i=0;i<c.length;i++){var l=c[i],s=a(l.querySelectorAll("li"));r(l)||s.some(r)?l.classList.remove("display-none"):l.classList.add("display-none")}});for(var e=document.querySelectorAll(".toggle-step-sibling"),t=0;t<e.length;t++)e[t].addEventListener("click",r);function n(e,t,n){e.classList.contains(n)?(e.classList.remove(n),t.innerHTML="▾"):(e.classList.add(n),t.innerHTML="▸")}function r(){var e=this.parentNode.parentNode.parentNode.querySelectorAll(".toggle-target")[0];n(e,e,"display-none")}for(var o=document.querySelectorAll("toggle-sibling"),i=0;i<o.length;i++)o[i].addEventListener("click",l);function l(){n(this.parentNode.querySelectorAll(".toggle-target")[0],this.querySelectorAll(".icon")[0],"display-none")}function s(e){var t=document.getElementById(e);t&&0===t.offsetHeight&&t.parentNode.parentNode.classList.contains("display-none")&&t.parentNode.parentNode.classList.remove("display-none")}window.addEventListener("hashchange",function(){s(location.hash.substring(1))}),s(location.hash.substring(1));for(var u=document.querySelectorAll(".pre-open"),f=0;f<u.length;f++)u[f].addEventListener("mousedown",p,!1);function p(){s(this.hash.substring(1))}var h=document.querySelector("#split-left"),y=document.querySelector("#split-right");function g(){history.replaceState({leftTop:h.scrollTop,rightTop:y.scrollTop},document.title)}function v(e){e&&history.replaceState(e.state,document.title),history.state&&(h.scrollTop=history.state.leftTop,y.scrollTop=history.state.rightTop)}h.style.overflow="hidden",h.style.overflow="",Split(["#split-left","#split-right"],{elementStyle:function(e,t,n){return{"flex-basis":"calc("+t+"% - "+n+"px)"}},gutterStyle:function(e,t){return{"flex-basis":t+"px"}},gutterSize:20,sizes:[20,80]}),window.addEventListener("load",function(){setTimeout(function(){v(),g(),h.addEventListener("scroll",g),y.addEventListener("scroll",g)},1)}),window.addEventListener("popstate",v)}();
diff --git a/docs/index.html b/docs/index.html
index d31eaa0..ea55a2f 100644
--- a/docs/index.html
+++ b/docs/index.html
@@ -212,7 +212,7 @@ <h2 id="api" class="m0">
   
   <div class='clearfix'>
     
-      <a class='pl3 pr1 right rounded github' href='https://github.com/MarkGriffiths/truwrap/blob/f5ef179217ba1e8e270a99856cfaab01fae2fcbd/src/index.js#L50-L218'>
+      <a class='pl3 pr1 right rounded github' href='https://github.com/MarkGriffiths/truwrap/blob/c23f02ad1434e9b46bee4b2a4d282697b96fa060/src/index.js#L50-L218'>
       <span>src/index.js</span>
       </a>
     
@@ -379,7 +379,7 @@ <h3 class='left m0 panel-title' id='truwrap'>
   
   <div class='clearfix'>
     
-      <a class='pl3 pr1 right rounded github' href='https://github.com/MarkGriffiths/truwrap/blob/f5ef179217ba1e8e270a99856cfaab01fae2fcbd/src/index.js#L100-L167'>
+      <a class='pl3 pr1 right rounded github' href='https://github.com/MarkGriffiths/truwrap/blob/c23f02ad1434e9b46bee4b2a4d282697b96fa060/src/index.js#L100-L167'>
       <span>src/index.js</span>
       </a>
     
@@ -435,7 +435,7 @@ <h3 class='left m0 panel-title' id='api'>
   
   <div class='clearfix'>
     
-      <a class='pl3 pr1 right rounded github' href='https://github.com/MarkGriffiths/truwrap/blob/f5ef179217ba1e8e270a99856cfaab01fae2fcbd/src/index.js#L107-L113'>
+      <a class='pl3 pr1 right rounded github' href='https://github.com/MarkGriffiths/truwrap/blob/c23f02ad1434e9b46bee4b2a4d282697b96fa060/src/index.js#L107-L113'>
       <span>src/index.js</span>
       </a>
     
@@ -500,7 +500,7 @@ <h3 class='left m0 panel-title' id='api'>
   
   <div class='clearfix'>
     
-      <a class='pl3 pr1 right rounded github' href='https://github.com/MarkGriffiths/truwrap/blob/f5ef179217ba1e8e270a99856cfaab01fae2fcbd/src/index.js#L119-L119'>
+      <a class='pl3 pr1 right rounded github' href='https://github.com/MarkGriffiths/truwrap/blob/c23f02ad1434e9b46bee4b2a4d282697b96fa060/src/index.js#L119-L119'>
       <span>src/index.js</span>
       </a>
     
@@ -565,7 +565,7 @@ <h3 class='left m0 panel-title' id='api'>
   
   <div class='clearfix'>
     
-      <a class='pl3 pr1 right rounded github' href='https://github.com/MarkGriffiths/truwrap/blob/f5ef179217ba1e8e270a99856cfaab01fae2fcbd/src/index.js#L128-L134'>
+      <a class='pl3 pr1 right rounded github' href='https://github.com/MarkGriffiths/truwrap/blob/c23f02ad1434e9b46bee4b2a4d282697b96fa060/src/index.js#L128-L134'>
       <span>src/index.js</span>
       </a>
     
@@ -653,7 +653,7 @@ <h3 class='left m0 panel-title' id='api'>
   
   <div class='clearfix'>
     
-      <a class='pl3 pr1 right rounded github' href='https://github.com/MarkGriffiths/truwrap/blob/f5ef179217ba1e8e270a99856cfaab01fae2fcbd/src/index.js#L142-L145'>
+      <a class='pl3 pr1 right rounded github' href='https://github.com/MarkGriffiths/truwrap/blob/c23f02ad1434e9b46bee4b2a4d282697b96fa060/src/index.js#L142-L145'>
       <span>src/index.js</span>
       </a>
     
@@ -733,7 +733,7 @@ <h3 class='left m0 panel-title' id='api'>
   
   <div class='clearfix'>
     
-      <a class='pl3 pr1 right rounded github' href='https://github.com/MarkGriffiths/truwrap/blob/f5ef179217ba1e8e270a99856cfaab01fae2fcbd/src/index.js#L152-L155'>
+      <a class='pl3 pr1 right rounded github' href='https://github.com/MarkGriffiths/truwrap/blob/c23f02ad1434e9b46bee4b2a4d282697b96fa060/src/index.js#L152-L155'>
       <span>src/index.js</span>
       </a>
     
@@ -798,7 +798,7 @@ <h3 class='left m0 panel-title' id='api'>
   
   <div class='clearfix'>
     
-      <a class='pl3 pr1 right rounded github' href='https://github.com/MarkGriffiths/truwrap/blob/f5ef179217ba1e8e270a99856cfaab01fae2fcbd/src/index.js#L163-L166'>
+      <a class='pl3 pr1 right rounded github' href='https://github.com/MarkGriffiths/truwrap/blob/c23f02ad1434e9b46bee4b2a4d282697b96fa060/src/index.js#L163-L166'>
       <span>src/index.js</span>
       </a>