diff --git a/docs/experiments/parsers/v4/core.js b/docs/experiments/parsers/v4/core.js
deleted file mode 100644
index f2283a7..0000000
--- a/docs/experiments/parsers/v4/core.js
+++ /dev/null
@@ -1,77 +0,0 @@
-import { useDocument } from '@terrace/core'
-import { createStringReader } from '@terrace/core/readers/js-string'
-
-export async function parse(lines) {
-  const { tail, each, match, buildObject } = useDocument(createStringReader(lines))
-
-  const structure = {
-    name: null,
-    version: null,
-    license: null,
-    exports: null,
-    scripts: null,
-    devDependencies: null,
-    author: null
-  }
-
-  await each(async () => {
-    if (match('name')) structure.name = tail().trim()
-    if (match('version')) structure.version = tail().trim()
-    if (match('license')) structure.license = tail().trim()
-    // FIXME: Order of operations causes other parts to break if this doesn't run first?!
-    if (match('exports')) structure.exports = await buildObject([], async () => {
-      const section = { import: null, require: null }
-
-      await each(() => {
-        if (match('import')) section.import = tail().trim()
-        if (match('require')) section.require = tail().trim()
-        if (section.import && section.require) return true
-      })
-
-      return section
-    })
-    if (match('scripts')) structure.scripts = await buildObject()
-    if (match('devDependencies')) structure.devDependencies = await buildObject()
-    if (match('author')) structure.author = await buildObject(['name', 'email', '#text'])
-
-    return structure.name &&
-      structure.version &&
-      structure.license &&
-      structure.exports &&
-      structure.scripts &&
-      structure.devDependencies &&
-      structure.author
-  })
-
-  return structure
-}
-
-export async function toArrays(lines) {
-  const { next, level, line } = useDocument(createStringReader(lines))
-
-  const levelTracker = []
-
-  function createScope(level, line) {
-    levelTracker.length = level
-    const scope = levelTracker[level] = [line, []]
-    return scope
-  }
-  createScope(0, 'root')
-
-  // Simple parser that produces canonical array structure for blocks.
-  while (true) {
-    // If next() returns true we've ended the document.
-    if (await next()) break;
-    // Determine parent for this scope.
-    const parent = levelTracker[level()]
-    // If there's no parent, skip this line.
-    if (!parent) continue
-
-    // Create new scope
-    const scope = createScope(level() + 1, line())
-    // Add current scope to parent.
-    parent[1].push(scope)
-  }
-
-  return levelTracker[0]
-}
diff --git a/docs/experiments/parsers/v4/example.js b/docs/experiments/parsers/v4/example.js
index 8be005d..5e5b5ed 100644
--- a/docs/experiments/parsers/v4/example.js
+++ b/docs/experiments/parsers/v4/example.js
@@ -1,40 +1,7 @@
-import { parse, toArrays } from './core.js'
+import { useDocument } from '@terrace/core'
+import { createStringReader } from '@terrace/core/readers/js-string'
 
-const linesArrays = [
-  `title Example`,
-  `options`,
-  ` parameter1 30`,
-  ` parameter2 Enim eu id anim minim reprehenderit nostrud eu amet deserunt ea ut do cupidatat ea.`,
-  `options`,
-  ` parameter1 0`,
-  ` parameter2 Esse incididunt et est adipisicing eiusmod aliqua enim ea aliqua id enim.`,
-  `  deep Enim fugiat do in est commodo culpa dolore.`,
-  `subsection`,
-  ` position 1`,
-  ` Ea dolore in aliquip fugiat anim adipisicing amet aute tempor et deserunt est duis sint.`,
-  `subsection 2`,
-  ` position 2`,
-  ` `,
-  ` Aute deserunt incididunt ad in sint adipisicing est officia velit pariatur ipsum deserunt quis nulla.`,
-  ` Ea dolore in aliquip fugiat anim adipisicing amet aute tempor et deserunt est duis sint.`,
-  `list`,
-  ` - item 1`,
-  ` - item 2`,
-  `collection`,
-  ` section`,
-  `  lorem ipsum 1`,
-  ` section`,
-  `  lorem ipsum 2`,
-  `collection2`,
-  ` section`,
-  `  position 3`,
-  `  Laborum aute anim occaecat occaecat pariatur tempor proident magna sit magna non non.`,
-  ` list`,
-  `  1`,
-  `  2`
-]
-
-const linesParse = [
+const lines = [
   `name @terrace/core`,
   `version 0.0.1`,
   `randomthing test`,
@@ -75,35 +42,53 @@ const linesParse = [
   ` way of dealing with this problem.`,
 ]
 
-const schema = {
-  "name": {count: 1},
-  "version": {count: 1},
-  "license": {count: 1},
-  "exports": {count: 1, children: {
-    "?": {count: -1, children: {
-      "import": {count: 1},
-      "require": {count: 1}
-    }}
-  }},
-  "scripts": {count: 1, children: {
-    "?": { count: -1 }
-  }},
-  "devDependencies": {count: 1, children: {
-    "?": { count: -1 }
-  }},
-  "author": { count: 1, children: {
-    "name": { count: 1 },
-    "email": { count: 1 },
-    "? literal": { count: -1 }
-  }}
-}
-
 async function main() {
-  const resultArrays = await toArrays(linesArrays)
-  // console.dir(resultArrays, { depth: null })
+  const { toArrays } = useDocument(createStringReader(lines))
+  const resultArrays = await toArrays()
+  console.dir(resultArrays, { depth: null })
 
-  const resultParse = await parse(linesParse)
-  console.dir(resultParse, { depth: null })
+  const { tail, each, match, buildObject } = useDocument(createStringReader(lines))
+
+  const structure = {
+    name: null,
+    version: null,
+    license: null,
+    exports: null,
+    scripts: null,
+    devDependencies: null,
+    author: null
+  }
+
+  await each(async () => {
+    if (match('name')) structure.name = tail().trim()
+    if (match('version')) structure.version = tail().trim()
+    if (match('license')) structure.license = tail().trim()
+    // FIXME: Order of operations causes other parts to break if this doesn't run first?!
+    if (match('exports')) structure.exports = await buildObject([], async () => {
+      const section = { import: null, require: null }
+
+      await each(() => {
+        if (match('import')) section.import = tail().trim()
+        if (match('require')) section.require = tail().trim()
+        if (section.import && section.require) return true
+      })
+
+      return section
+    })
+    if (match('scripts')) structure.scripts = await buildObject()
+    if (match('devDependencies')) structure.devDependencies = await buildObject()
+    if (match('author')) structure.author = await buildObject(['name', 'email', '#text'])
+
+    return structure.name &&
+      structure.version &&
+      structure.license &&
+      structure.exports &&
+      structure.scripts &&
+      structure.devDependencies &&
+      structure.author
+  })
+
+  console.dir(structure, { depth: null })
 }
 
 main()
diff --git a/packages/js/core/dist/document.cjs b/packages/js/core/dist/document.cjs
index d79e3a6..bf6ea3e 100644
--- a/packages/js/core/dist/document.cjs
+++ b/packages/js/core/dist/document.cjs
@@ -1 +1 @@
-"use strict";Object.defineProperties(exports,{__esModule:{value:!0},[Symbol.toStringTag]:{value:"Module"}});const s=require("./parser.cjs");function c(a,u=" "){let r=s.createLineData(null,u);const t={ended:!1,clone(){return c(a.clone(),u)},async next(){if(r.line=await a.next(),r.line===null)return!0;s.parseLine(r)},current(){return t},line(){var e;return(e=r.line)==null?void 0:e.slice(r.offsetHead)},head(){var e;return(e=r.line)==null?void 0:e.slice(r.offsetHead,r.offsetTail)},tail(){var e;return(e=r.line)==null?void 0:e.slice(r.offsetTail)},level(){return r.level},async content(e=-1,n=[]){var l;return e===-1&&(e=r.level+1),await t.next()||r.level<e?n:(n.push(((l=r.line)==null?void 0:l.slice(e))||""),t.content(e,n))},match(e){return e===t.head()},async each(e){const n=t.line()!==void 0?t.level():-1;for(;!(await t.next()||t.level()<=n||await e()););},async buildObject(e=[],n){n||(n=()=>t.tail().trim());const i={};return await t.each(async()=>{if(!!t.head()){if(!e.length||e.includes(t.head())){i[t.head()]=await n();return}if(e&&!e.includes(t.head())&&e.includes("#text")){i["#text"]=[t.line(),...await t.content(t.level())];return}}}),i},async seek(e,n=-1){return n===-1&&(n=r.level),await t.next()?!1:t.head()===e?t:r.level<n?!1:t.seek(e,n)}};return t}exports.useDocument=c;
+"use strict";Object.defineProperties(exports,{__esModule:{value:!0},[Symbol.toStringTag]:{value:"Module"}});const h=require("./parser.cjs");function T(p,b=" "){let c=0;const t=h.createLineData("",b);async function s(){c===0&&(c=1);const e=await p.next();return e===null?(c=2,!0):(t.line=e,h.parseLine(t),!1)}const a=()=>t.level,u=()=>t.line.slice(t.offsetHead),o=()=>t.line.slice(t.offsetHead,t.offsetTail),f=()=>t.line.slice(t.offsetTail),v=e=>e===o();async function d(e){const n=c===0?-1:a();for(;!(await s()||a()<=n||await e()););}async function l(e=-1,n=[u()]){var i;return e===-1&&(e=t.level+1),await s()||t.level<e?n:(n.push(((i=t.line)==null?void 0:i.slice(e))||""),l(e,n))}async function w(e=[],n){const r={};return await d(async()=>{const i=o();if(!!i){if(!e.length||e.includes(i)){r[i]=n?await n():f().trim();return}if(e&&!e.includes(i)&&e.includes("#text")){r["#text"]=await l(a());return}}}),r}async function m(){const e=[["root",[]]];for(;!await s();){const n=a(),r=n+1,i=e[n];if(!i)continue;e.length=r;const x=e[r]=[u(),[]];i[1].push(x)}return e[0]}return{state:c,next:s,line:u,head:o,tail:f,level:a,match:v,each:d,blockAsText:l,buildObject:w,toArrays:m}}exports.useDocument=T;
diff --git a/packages/js/core/dist/document.js b/packages/js/core/dist/document.js
index a9f8db0..e215aa4 100644
--- a/packages/js/core/dist/document.js
+++ b/packages/js/core/dist/document.js
@@ -1,68 +1,64 @@
-import { parseLine as f, createLineData as s } from "./parser.js";
-function c(a, u = " ") {
-  let n = s(null, u);
-  const t = {
-    ended: !1,
-    clone() {
-      return c(a.clone(), u);
-    },
-    async next() {
-      if (n.line = await a.next(), n.line === null)
-        return !0;
-      f(n);
-    },
-    current() {
-      return t;
-    },
-    line() {
-      var e;
-      return (e = n.line) == null ? void 0 : e.slice(n.offsetHead);
-    },
-    head() {
-      var e;
-      return (e = n.line) == null ? void 0 : e.slice(n.offsetHead, n.offsetTail);
-    },
-    tail() {
-      var e;
-      return (e = n.line) == null ? void 0 : e.slice(n.offsetTail);
-    },
-    level() {
-      return n.level;
-    },
-    async content(e = -1, r = []) {
-      var l;
-      return e === -1 && (e = n.level + 1), await t.next() || n.level < e ? r : (r.push(((l = n.line) == null ? void 0 : l.slice(e)) || ""), t.content(e, r));
-    },
-    match(e) {
-      return e === t.head();
-    },
-    async each(e) {
-      const r = t.line() !== void 0 ? t.level() : -1;
-      for (; !(await t.next() || t.level() <= r || await e()); )
-        ;
-    },
-    async buildObject(e = [], r) {
-      r || (r = () => t.tail().trim());
-      const i = {};
-      return await t.each(async () => {
-        if (!!t.head()) {
-          if (!e.length || e.includes(t.head())) {
-            i[t.head()] = await r();
-            return;
-          }
-          if (e && !e.includes(t.head()) && e.includes("#text")) {
-            i["#text"] = [t.line(), ...await t.content(t.level())];
-            return;
-          }
+import { parseLine as v, createLineData as T } from "./parser.js";
+function y(h, p = " ") {
+  let r = 0;
+  const t = T("", p);
+  async function s() {
+    r === 0 && (r = 1);
+    const e = await h.next();
+    return e === null ? (r = 2, !0) : (t.line = e, v(t), !1);
+  }
+  const a = () => t.level, o = () => t.line.slice(t.offsetHead), u = () => t.line.slice(t.offsetHead, t.offsetTail), l = () => t.line.slice(t.offsetTail), w = (e) => e === u();
+  async function d(e) {
+    const n = r === 0 ? -1 : a();
+    for (; !(await s() || a() <= n || await e()); )
+      ;
+  }
+  async function f(e = -1, n = [o()]) {
+    var i;
+    return e === -1 && (e = t.level + 1), await s() || t.level < e ? n : (n.push(((i = t.line) == null ? void 0 : i.slice(e)) || ""), f(e, n));
+  }
+  async function x(e = [], n) {
+    const c = {};
+    return await d(async () => {
+      const i = u();
+      if (!!i) {
+        if (!e.length || e.includes(i)) {
+          c[i] = n ? await n() : l().trim();
+          return;
         }
-      }), i;
-    },
-    async seek(e, r = -1) {
-      return r === -1 && (r = n.level), await t.next() ? !1 : t.head() === e ? t : n.level < r ? !1 : t.seek(e, r);
+        if (e && !e.includes(i) && e.includes("#text")) {
+          c["#text"] = await f(a());
+          return;
+        }
+      }
+    }), c;
+  }
+  async function b() {
+    const e = [["root", []]];
+    for (; !await s(); ) {
+      const n = a(), c = n + 1, i = e[n];
+      if (!i)
+        continue;
+      e.length = c;
+      const m = e[c] = [o(), []];
+      i[1].push(m);
     }
+    return e[0];
+  }
+  return {
+    state: r,
+    next: s,
+    line: o,
+    head: u,
+    tail: l,
+    level: a,
+    match: w,
+    each: d,
+    blockAsText: f,
+    buildObject: x,
+    toArrays: b
   };
-  return t;
 }
 export {
-  c as useDocument
+  y as useDocument
 };
diff --git a/packages/js/core/dist/parser.cjs b/packages/js/core/dist/parser.cjs
index 7d0ab01..16bf37d 100644
--- a/packages/js/core/dist/parser.cjs
+++ b/packages/js/core/dist/parser.cjs
@@ -1 +1 @@
-"use strict";Object.defineProperties(exports,{__esModule:{value:!0},[Symbol.toStringTag]:{value:"Module"}});function f(e=null,r=" "){return{line:e,indent:r,type:0,level:0,offsetHead:0,offsetTail:0}}function o(e){if(typeof e!="object"||!e||typeof e.type!="number"||typeof e.level!="number")throw new Error("'lineData' must be an object with 'line' string, and 'type' and 'level' integer properties");if(typeof e.indent!="string"||e.indent.length===0||e.indent.length>1)throw new Error("'lineData.indent' must be a single-character string");if(typeof e.line!="string")throw new Error("'lineData.line' must be a string");let r=0,t=0;if(!e.line.length)e.type===1&&(t+=1),e.type===0&&(t=e.level),e.type=r,e.level=t,e.offsetHead=0,e.offsetTail=0;else{for(r=1;e.line[t]===e.indent&&t<=e.level+1;)++t;for(e.type=r,e.level=t,e.offsetHead=t,e.offsetTail=t;e.line[e.offsetTail]&&e.line[e.offsetTail]!==" ";)++e.offsetTail}return e}exports.createLineData=f;exports.parseLine=o;
+"use strict";Object.defineProperties(exports,{__esModule:{value:!0},[Symbol.toStringTag]:{value:"Module"}});function f(e="",r=" "){return{line:e,indent:r,type:0,level:0,offsetHead:0,offsetTail:0}}function o(e){if(typeof e!="object"||!e||typeof e.type!="number"||typeof e.level!="number")throw new Error("'lineData' must be an object with 'line' string, and 'type' and 'level' integer properties");if(typeof e.indent!="string"||e.indent.length===0||e.indent.length>1)throw new Error("'lineData.indent' must be a single-character string");if(typeof e.line!="string")throw new Error("'lineData.line' must be a string");let r=0,t=0;if(!e.line.length)e.type===1&&(t+=1),e.type===0&&(t=e.level),e.type=r,e.level=t,e.offsetHead=0,e.offsetTail=0;else{for(r=1;e.line[t]===e.indent&&t<=e.level+1;)++t;for(e.type=r,e.level=t,e.offsetHead=t,e.offsetTail=t;e.line[e.offsetTail]&&e.line[e.offsetTail]!==" ";)++e.offsetTail}return e}exports.createLineData=f;exports.parseLine=o;
diff --git a/packages/js/core/dist/parser.js b/packages/js/core/dist/parser.js
index 4e8c666..f0ee311 100644
--- a/packages/js/core/dist/parser.js
+++ b/packages/js/core/dist/parser.js
@@ -1,4 +1,4 @@
-function t(e = null, r = " ") {
+function t(e = "", r = " ") {
   return { line: e, indent: r, type: 0, level: 0, offsetHead: 0, offsetTail: 0 };
 }
 function o(e) {
diff --git a/packages/js/core/package.json b/packages/js/core/package.json
index 9a3d976..a8a5568 100644
--- a/packages/js/core/package.json
+++ b/packages/js/core/package.json
@@ -27,6 +27,7 @@
   },
   "scripts": {
     "test": "vitest ./src",
+    "dev": "vite build --watch",
     "build": "vite build"
   },
   "devDependencies": {
diff --git a/packages/js/core/src/document.ts b/packages/js/core/src/document.ts
index fd6a218..ddbe6d1 100644
--- a/packages/js/core/src/document.ts
+++ b/packages/js/core/src/document.ts
@@ -1,117 +1,131 @@
 import type { Reader } from './readers/reader'
 import { createLineData, parseLine } from './parser'
 
+enum STATE {
+  READY = 0,
+  STARTED = 1,
+  ENDED = 2
+}
+
 type Document = {
-  ended: boolean,
-  clone: () => Document,
-  next: () => Promise<Document>
-  current: () => Document
+  state: STATE,
+  next: () => Promise<boolean>
+  level: () => number,
   line: () => string,
   head: () => string,
   tail: () => string,
-  content: (contentLevel: number, lines: string[]) => Promise<string>,
   match: (matchHead: string) => boolean,
   each: (handler: Function) => void,
-  buildObject: (allowList: Array<string>, handler: Function) => object,
-  seek: (matchHead: string, contentLevel: number) => Promise<Document|false>
+  blockAsText: (startLevel: number, lines?: string[]) => Promise<Array<string>>,
+  buildObject: (allowKeys: Array<string>, processValue?: () => any) => any,
+  toArrays(): Promise<LineArray>
 }
 
+type LineArray = [string, Array<LineArray>];
+
 export function useDocument (reader: Reader, indent: string = ' '): Document {
-  let lineData = createLineData(null, indent)
+  let state = STATE.READY
+  const lineData = createLineData('', indent)
 
-  const document = {
-    ended: false,
+  async function next() {
+    if (state === STATE.READY) state = STATE.STARTED
 
-    clone() {
-      return useDocument(reader.clone(), indent)
-    },
+    const line = await reader.next()
+    if (line === null) {
+      state = STATE.ENDED
+      return true
+    }
 
-    async next() {
-      lineData.line = await reader.next()
-      if (lineData.line === null) return true
-      else parseLine(lineData)
-    },
+    lineData.line = line
+    parseLine(lineData)
+    return false
+  }
 
-    current() {
-      return document
-    },
+  const level = () => lineData.level
+  const line = () => lineData.line.slice(lineData.offsetHead)
+  const head = () => lineData.line.slice(lineData.offsetHead, lineData.offsetTail)
+  const tail = () => lineData.line.slice(lineData.offsetTail)
+  const match = (matchHead: string): boolean => matchHead === head()
 
-    line() {
-      return lineData.line?.slice(lineData.offsetHead)
-    },
+  async function each(handler: Function) {
+    // Set startLevel to -1 if we haven't started parsing the document yet.
+    // Otherwise we'll break to early, as the default value for doc.level() is 0.
+    const startLevel = state === STATE.READY ? -1 : level()
 
-    head () {
-      return lineData.line?.slice(lineData.offsetHead, lineData.offsetTail)
-    },
-
-    tail () {
-      return lineData.line?.slice(lineData.offsetTail)
-    },
-
-    level () {
-      return lineData.level
-    },
-
-    async content (contentLevel = -1, lines: string[] = []): Promise<Array<string>> {
-      if (contentLevel === -1) contentLevel = lineData.level + 1
-
-      const ended = await document.next()
-      if (ended) return lines
-
-      if (lineData.level < contentLevel) return lines
-
-      lines.push(lineData.line?.slice(contentLevel) || '')
-      return document.content(contentLevel, lines)
-    },
-
-    match(matchHead: string): boolean {
-      return matchHead === document.head()
-    },
-
-    async each(handler: Function) {
-      // Set startLevel to -1 if we haven't started parsing the document yet.
-      // Otherwise we'll break to early, as the default value for doc.level() is 0.
-      const startLevel = document.line() !== undefined ? document.level() : -1
-
-      while(true) {
-        if (await document.next()) break
-        if (document.level() <= startLevel) break
-        if (await handler()) break
-      }
-    },
-
-    async buildObject(allowList = [], valHandler?: () => any) {
-      if (!valHandler) valHandler = () => document.tail().trim()
-
-      const obj = {}
-      await document.each(async () => {
-        if (!document.head()) return
-        if (!allowList.length || allowList.includes(document.head())) {
-          obj[document.head()] = await valHandler()
-          return
-        }
-
-        // Parse unspecified text into an array of lines and save to #text key.
-        if (allowList && !allowList.includes(document.head()) && allowList.includes('#text')) {
-          obj['#text'] = [document.line(), ...await document.content(document.level())]
-          return
-        }
-      })
-      return obj
-    },
-
-    async seek (matchHead: string, contentLevel = -1): Promise<Document|false> {
-      if (contentLevel === -1) contentLevel = lineData.level
-
-      const ended = await document.next()
-      if (ended) return false
-
-      if (document.head() === matchHead) return document
-      if (lineData.level < contentLevel) return false
-
-      return document.seek(matchHead, contentLevel)
+    while(true) {
+      if (await next()) break
+      if (level() <= startLevel) break
+      if (await handler()) break
     }
   }
 
-  return document
+  async function blockAsText (startLevel: number = -1, blockLines: string[] = [line()]): Promise<Array<string>> {
+    if (startLevel === -1) startLevel = lineData.level + 1
+
+    const ended = await next()
+    if (ended) return blockLines
+    if (lineData.level < startLevel) return blockLines
+
+    blockLines.push(lineData.line?.slice(startLevel) || '')
+    return blockAsText(startLevel, blockLines)
+  }
+
+  async function buildObject(allowKeys: Array<string> = [], processValue?: () => any) {
+    const obj: any = {}
+    await each(async () => {
+      const currHead = head()
+      if (!currHead) return
+      // Set the object key matching the current head if it is allowed, or if no allow list is specified.
+      if (!allowKeys.length || allowKeys.includes(currHead)) {
+        // Default to using {head: tail} as the key-value pair if no value handler is specified.
+        obj[currHead] = processValue ? await processValue() : tail().trim()
+        return
+      }
+
+      // Parse unspecified text into an array of lines and save to #text key.
+      // TODO: Rework this. I don't like it at all.
+      if (allowKeys && !allowKeys.includes(currHead) && allowKeys.includes('#text')) {
+        obj['#text'] = await blockAsText(level())
+        return
+      }
+    })
+    return obj
+  }
+
+  async function toArrays(): Promise<LineArray> {
+    const levelTracker: Array<LineArray> = [['root', []]]
+
+    // Simple parser that produces canonical array structure for blocks.
+    while (true) {
+      // If next() returns true we've ended the
+      if (await next()) break;
+      const parentLevel = level()
+      const scopeLevel = parentLevel + 1
+      // Determine parent for this scope.
+      const parent = levelTracker[parentLevel]
+      // If there's no parent, skip this line.
+      if (!parent) continue
+
+      levelTracker.length = scopeLevel
+      const scope = levelTracker[scopeLevel] = [line(), []]
+      // Add current scope to parent.
+      parent[1].push(scope)
+    }
+
+    return levelTracker[0]
+  }
+
+  return {
+    state,
+    next,
+    line,
+    head,
+    tail,
+    level,
+    match,
+    each,
+    blockAsText,
+    buildObject,
+    toArrays,
+  }
 }
diff --git a/packages/js/core/src/parser.ts b/packages/js/core/src/parser.ts
index 0522255..f3913ac 100644
--- a/packages/js/core/src/parser.ts
+++ b/packages/js/core/src/parser.ts
@@ -1,5 +1,5 @@
 export type LineData = {
-  line: string|null;
+  line: string;
   indent: string;
   type: number;
   level: number;
@@ -7,7 +7,7 @@ export type LineData = {
   offsetTail: number;
 }
 
-export function createLineData(line: string|null = null, indent: string = ' '): LineData {
+export function createLineData(line: string = '', indent: string = ' '): LineData {
   return { line, indent, type: 0, level: 0, offsetHead: 0, offsetTail: 0 }
 }