Lodash _.templateSettings

What Is _.templateSettings?

The default settings object used by _.template() for delimiters (escape, evaluate, interpolate), free-variable imports, and the data variable name. Part of Lodash Properties (stable in 4.x — not deprecated). Warning: _.template compiles executable code — never use untrusted template strings; Lodash plans to remove it in v5.

_.templateSettings

// Defaults used by _.template(string, [options])
// options on _.template() override these values

escape       // RegExp → <%- value %>  (HTML-escaped)
interpolate  // RegExp → <%= value %>  (raw insert)
evaluate     // RegExp → <% code %>    (run JS)
imports      // Object of free variables (includes _)
variable     // data object name (optional)

How to Use _.templateSettings

Set defaults before compiling, or pass options to _.template() for a one-off override.

1. Decide which delimiters or helpers you need.
2. Either assign on _.templateSettings, or pass matching keys in _.template(string, options).
3. Compile with _.template(string).
4. Call the compiled function with a data object.
5. If you changed global settings temporarily, restore the previous values.

Pseudocode

settings = merge(_.templateSettings, options)
compiled = compile(templateString, settings)
return function (data) {
    return render(compiled, data, settings.imports)
}

Cheat Sheet

Keep these facts handy when configuring templates.

Live Preview

Run presets inspired by the official _.template docs (settings restore after each run).

_.templateSettings.interpolate = /{{([\s\S]+?)}}/g
→ "hello mustache!"

Worked Walkthrough — Custom Interpolate

Trace the official custom delimiters example: change interpolate, compile, render, then restore.

save = _.templateSettings.interpolate

_.templateSettings.interpolate = /{{([\s\S]+?)}}/g
compiled = _.template('hello {{ user }}!')
compiled({ user: 'mustache' })
→ "hello mustache!"

_.templateSettings.interpolate = save
// later compiles use defaults again

Lodash Examples

Short, copy-ready snippets from the official _.template docs. Open DevTools, or use Try It Yourself for a live editor.

_.templateSettings.interpolate = /{{([\s\S]+?)}}/g;
var compiled = _.template('hello {{ user }}!');
compiled({ 'user': 'mustache' });
// → 'hello mustache!'

hello mustache!

var compiled = _.template('hello <%= user %>!');
compiled({ 'user': 'fred' });
// → 'hello fred!'

hello fred!

var compiled = _.template('<b><%- value %></b>');
compiled({ 'value': '<script>' });
// → '<b>&lt;script&gt;</b>'

<b>&lt;script&gt;</b>

var compiled = _.template(
  '<% _.forEach(users, function(user) { %>' +
    '<li><%- user %></li>' +
  '<% }); %>'
);
compiled({ 'users': ['fred', 'barney'] });
// → '<li>fred</li><li>barney</li>'

<li>fred</li><li>barney</li>

var compiled = _.template(
  'hi <%= data.user %>!',
  { 'variable': 'data' }
);
compiled({ 'user': 'fred' });
// → 'hi fred!'

// compiled.source uses function(data) { ... }
// instead of with(obj) { ... }

hi fred!

Performance Notes

Changing settings is cheap; compiling is the expensive step. Compile once and reuse the function.

Key Takeaways