Convert a string to a template string

Question

Is it possible to create a template string as a usual string

let a=\"b:${b}\";

an then convert it into a template string

le         


        

Answer 1

Similar to Daniel's answer (and s.meijer's gist) but more readable:

const regex = /\${[^{]+}/g;

export default function interpolate(template, variables, fallback) {
    return template.replace(regex, (match) => {
        const path = match.slice(2, -1).trim();
        return getObjPath(path, variables, fallback);
    });
}

//get the specified property or nested property of an object
function getObjPath(path, obj, fallback = '') {
    return path.split('.').reduce((res, key) => res[key] || fallback, obj);
}

Note: This slightly improves s.meijer's original, since it won't match things like ${foo{bar} (the regex only allows non-curly brace characters inside ${ and }).

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UPDATE: I was asked for an example using this, so here you go:

const replacements = {
    name: 'Bob',
    age: 37
}

interpolate('My name is ${name}, and I am ${age}.', replacements)