How to implement a recursion rule in ace editor?

I need to highlight ${} in a string, and if ${} has a word "baseMembers", it need to be highlighted by different color too, like: enter image description here

How could I accomplish this? Thanks.

please see the pic above.

One of the ways to do it is like this: you push a state that's like your regular start-state but has an exit condition (and pushes itself again on { so that it supports nested brackets)

var oop = require("../lib/oop");
var TextHighlightRules = require("./text_highlight_rules").TextHighlightRules;

var HighlightRules = function() {
    var start = [
        { regex: "//.*", token: "comment" },
        { regex: "\\d+", token: "constant.numeric" },
        { regex: '\\$"', token: "string", push: "string" },
        { defaultToken: "text" }
    ];
    this.$rules = {
        start: start,
        string_expr: [
            { regex: '\\{', token: "curly.paren.lparen", push: "string_expr" },
            { regex: '\\}', token: "curly.paren.rparen", next: "pop" },
        ].concat(start),
        string: [
            { regex: "\\{", token: "string", push: "string_expr" },
            { regex: '"', token: "string", next: "pop" },
            { defaultToken: "string" }
        ]
    };

    this.normalizeRules();
};

oop.inherits(HighlightRules, TextHighlightRules);