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Version: 3.x.x

Template Syntax

Eta's syntax will be familiar if you've ever used EJS. You'll get the hang of it in no time!

Basic Syntax

The data you pass in is available in the it variable.

To output data, use the <%= opening tag.

Hi <%= %>

By default, Eta will automatically XML-escape the data you output. To allow raw HTML, use the <%~ opening tag.

Hi <%~ it.contentContainingHTML %>

To evaluate JavaScript, use the <% opening tag.

<% let myVar = 3 %>

Comments are just like regular JavaScript multiline comments!

<% /* this is a comment */ %>

Partials and Layouts

Partials are just like regular templates, except they are rendered inside other templates.

To render a partial, use the <%~ opening tag + the include() function.

<%~ include("./path-to-partial") %>
<% /* we can also pass in data that will be merged with `it` and passed to the partial */ %>
<%~ include("./path-to-partial", { option: true }) %>

To render an async partial, use the <%~ opening tag + the includeAsync() function.

<%~ await includeAsync("./path-to-partial") %>

A template file can only have one parent layout (though layouts themselves can have parents). To set the parent layout, use the layout() function.

<% layout("./path-to-layout") %>

To render child content in the layout, use it.body.

<%~ it.body %>

Name Resolution of Partials and Layouts

If you're running Eta in Node.js or Deno, Eta will automatically try to resolve partials and layouts from inside the filesystem. Ex. <%~ include("/header.eta") %> will look for a file called header.eta in the views directory of your project.

But what if you want to include a partial/layout that doesn't exist on the filesystem? Maybe you programatically defined it as a string or loaded it from the internet. There's a solution for that. If you name your template starting with an @ symbol, Eta will know to look in the internal template storage rather than on the filesystem.

<%~ include("@header") %>

Whitespace Control

Note: a "delimiter" means the opening or closing tag.

Opening delimiters can be followed with - or _, and closing delimiters can be prefixed with - or _

_ at the beginning of a tag will trim all whitespace before it, and _ at the end of a tag will trim all whitespace after it.

- at the beginning of a tag will trim 1 newline before it, and - at the end of a tag will trim 1 newline after it.

<%- = it.myname %>
<% /* %The newline after "Hi" will be stripped */ %>