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\n ```\n\n - Void *attributes*\n\n ``` html\n \n ```\n\n - Normal *attributes*\n\n ``` html\n \n ```\n\n## Install\n\n```\nnpm install html-tag-validator\n```\n\n## Usage\n\nThe library exposes a single function that accepts two arguments: a string\ncontaining HTML, and a callback function. The callback should be in the form:\n\n``` javascript\nfunction (err, ast) {\n if (err) {\n // View the error generated by the parser\n console.log(err.message);\n } else {\n // View a the AST generated by the parser\n console.log(ast);\n }\n}\n```\n\n### Default syntax\n\n``` javascript\nvar htmlTagValidator = require('html-tag-validator'),\n sampleHtml = \"\" +\n \"my cool page
\" +\n \"\";\n\n// Turn a HTML string into an AST\nhtmlTagValidator(sampleHtml, function (err, ast) {\n if (err) {\n throw err;\n } else {\n console.log(ast);\n }\n});\n```\n\nProduces the following AST:\n\n```\ndoctype: null\ndocument:\n -\n type: element\n void: false\n name: html\n attributes: {}\n\n children:\n -\n type: element\n void: false\n name: head\n attributes: {}\n\n children:\n -\n type: title\n attributes: {}\n\n contents: hello world\n -\n type: element\n void: false\n name: body\n attributes: {}\n\n children:\n -\n type: element\n void: false\n name: p\n attributes:\n style: color: pink;\n children:\n -\n type: text\n contents: my cool page\n```\n\n### Passing in options\n\nCurrently, you can provide custom attribute names to merge with the default\nvalues, custom validation rules, and global settings such as the output format\nfor the validation messages.\n\n``` javascript\nvar htmlTagValidator = require('html-tag-validator'),\n sampleHtml = \"\" +\n \"\" +\n \"my cool page\" +\n \"
\" +\n \"\" +\n \"\";\n\n/*\n* Allow Angular 2 style attributes on all elements. The key '_' means match\n* on ANY tag, but you could also specific specific tag names (e.g.:\n* 'my-custom-tag'). Custom attributes for existing HTML 5 tags will be merged\n* with the official list of allowed tags. The key 'mixed' means normal or void\n* attributes for the given tag name. You can also specify to target all 'normal'\n* and/or 'void' attributes.\n*\n* This options object says the following:\n* for all existing HTML 5 tag names '_' ...\n* allow the following types of attribute names\n* 1) *ngSomething\n* 2) (something) \n* 3) [something] \n* 4) [(something)]\n* for void (e.g.: async) attributes OR\n* normal attributes (e.g.: checked=\"checked\") ...\n* in addition to the standard HTML 5 attributes for the element.\n* Also, this adds a new normal (not self-closing) tag named\n* template to support Angular 2 tags.\n*/\nhtmlTagValidator(sampleHtml, {\n settings: {\n // Set output format for validation error messages\n format: 'plain', // 'plain', 'html', or 'markdown'\n /* Setting verbose to true will generate an AST with additional\n * details such as whether tag attributes are unquoted */\n verbose: false, // default: false\n /* Set preserveCase to true to preserve the original case of tag and\n * attribute names so that you can support case-sensitive Angular 2\n * attribute names such as *ngFor and [ngModel] */\n preserveCase: true // default: false\n },\n tags: {\n normal: [ 'template' ]\n },\n attributes: {\n '_': {\n mixed: /^((\\*ng)|(^\\[[\\S]+\\]$)|(^\\([\\S]+\\)$))|(^\\[\\([\\S]+\\)\\]$)/\n }\n }\n}, function (err, ast) {\n if (err) {\n throw err;\n } else {\n console.log(ast);\n }\n});\n```\n\n``` javascript\nvar htmlTagValidator = require('html-tag-validator'),\n sampleHtml = \"\" +\n \"my cool page
\" +\n \"\";\n\n/*\n* Allow old-style HTML table attributes on specific elements.\n*\n* This options object adds some old HTML attributes for tables, to\n* the 'table' and 'td' elements, in addition to the standard HTML 5\n* attributes. Because the key is 'normal', these attributes are\n* validated as normal attributes that should have a defined value.\n*