source: node_modules/prismjs/components/prism-parser.js

(function (Prism) {

        var parser = Prism.languages.parser = Prism.languages.extend('markup', {
                'keyword': {
                        pattern: /(^|[^^])(?:\^(?:case|eval|for|if|switch|throw)\b|@(?:BASE|CLASS|GET(?:_DEFAULT)?|OPTIONS|SET_DEFAULT|USE)\b)/,
                        lookbehind: true
                },
                'variable': {
                        pattern: /(^|[^^])\B\$(?:\w+|(?=[.{]))(?:(?:\.|::?)\w+)*(?:\.|::?)?/,
                        lookbehind: true,
                        inside: {
                                'punctuation': /\.|:+/
                        }
                },
                'function': {
                        pattern: /(^|[^^])\B[@^]\w+(?:(?:\.|::?)\w+)*(?:\.|::?)?/,
                        lookbehind: true,
                        inside: {
                                'keyword': {
                                        pattern: /(^@)(?:GET_|SET_)/,
                                        lookbehind: true
                                },
                                'punctuation': /\.|:+/
                        }
                },
                'escape': {
                        pattern: /\^(?:[$^;@()\[\]{}"':]|#[a-f\d]*)/i,
                        alias: 'builtin'
                },
                'punctuation': /[\[\](){};]/
        });

        parser = Prism.languages.insertBefore('parser', 'keyword', {
                'parser-comment': {
                        pattern: /(\s)#.*/,
                        lookbehind: true,
                        alias: 'comment'
                },
                'expression': {
                        // Allow for 3 levels of depth
                        pattern: /(^|[^^])\((?:[^()]|\((?:[^()]|\((?:[^()])*\))*\))*\)/,
                        greedy: true,
                        lookbehind: true,
                        inside: {
                                'string': {
                                        pattern: /(^|[^^])(["'])(?:(?!\2)[^^]|\^[\s\S])*\2/,
                                        lookbehind: true
                                },
                                'keyword': parser.keyword,
                                'variable': parser.variable,
                                'function': parser.function,
                                'boolean': /\b(?:false|true)\b/,
                                'number': /\b(?:0x[a-f\d]+|\d+(?:\.\d*)?(?:e[+-]?\d+)?)\b/i,
                                'escape': parser.escape,
                                'operator': /[~+*\/\\%]|!(?:\|\|?|=)?|&&?|\|\|?|==|<[<=]?|>[>=]?|-[fd]?|\b(?:def|eq|ge|gt|in|is|le|lt|ne)\b/,
                                'punctuation': parser.punctuation
                        }
                }
        });

        Prism.languages.insertBefore('inside', 'punctuation', {
                'expression': parser.expression,
                'keyword': parser.keyword,
                'variable': parser.variable,
                'function': parser.function,
                'escape': parser.escape,
                'parser-punctuation': {
                        pattern: parser.punctuation,
                        alias: 'punctuation'
                }
        }, parser['tag'].inside['attr-value']);

}(Prism));