# Horrorshow
[](https://docs.rs/horrorshow/)
[](https://crates.io/crates/horrorshow)
A macro-based html templating library, compatible with stable rust (currently requires rust >= 1.48).
## Features
This crate will degrade gracefully when compiled without `std` (disable the "std"
feature) and even without `alloc` (disable the "alloc" feature).
When compiled with `alloc` but without `std`:
* `Template::write_to_io()` is not defined.
* Templates may only emit errors implementing `ToString` and all such errors are
immediately converted to strings.
When compiled with just core:
* `RenderBox` is no longer defined (no allocation).
* The `Template::into_string()` and `Template::write_to_string()` are no longer
defined. The only template rendering method available is
`Template::write_to_fmt()`.
* Templates may only emit static `&str` errors, and only the first is recorded.
## Example:
```rust
#[macro_use]
extern crate horrorshow;
use horrorshow::prelude::*;
use horrorshow::helper::doctype;
fn main() {
let actual = format!("{}", html! {
: doctype::HTML;
html {
head {
title : "Hello world!";
}
body {
// attributes
h1(id="heading") {
// Insert escaped text
: "Hello! This is <html />"
}
p {
// Insert raw text (unescaped)
: Raw("Let's <i>count</i> to 10!")
}
ol(id="count") {
// You can embed for loops, while loops, and if statements.
@ for i in 0..10 {
li(first? = (i == 0)) {
// Format some text.
: format_args!("{}", i+1)
}
}
}
// You need semi-colons for tags without children.
br; br;
p {
// You can also embed closures.
|tmpl| {
tmpl << "Easy!";
}
}
}
}
});
let expected = "\
<!DOCTYPE html>\
<html>\
<head>\
<title>Hello world!</title>\
</head>\
<body>\
<h1 id=\"heading\">Hello! This is <html /></h1>\
<p>Let's <i>count</i> to 10!</p>\
<ol id=\"count\">\
<li first>1</li>\
<li>2</li>\
<li>3</li>\
<li>4</li>\
<li>5</li>\
<li>6</li>\
<li>7</li>\
<li>8</li>\
<li>9</li>\
<li>10</li>\
</ol>\
<br><br>\
<p>Easy!</p>\
</body>\
</html>";
assert_eq!(expected, actual);
}
```