# template-eyre
An error reporter for panics and `eyre::Report` with handlebars template support.
Ever used [eyre](https://github.com/yaahc/eyre) and finding existing handlers too boring or complex?
This crate enables you to customize your error report and add custom fields
in seconds.
## Features
- [x] Handlebars powered error reports
- [x] Color support
- [x] Custom indent support
- [x] Sensible bundled handlers
- [ ] Backtrace support
- [ ] Panic handler
- [x] Custom fields support
## Write your own template
This crate includes two templates `Hook::simple` and `Hook::colored_simple`,
but you can always create your own templates easily!
First, get started by reading the [handlebars guide](https://handlebarsjs.com/guide/).
Handlebars is a simple template language, so this won't be hard.
Next, start writing your own template! You may gain some idea from [builtin templates](src/templates/).
Notice that this crate provides you with [some handy helpers](#additional-helpers).
Also, the `handlebars` crate this crate depends on also has some [custom helpers](https://docs.rs/handlebars/latest/handlebars/#built-in-helpers).
## Example
A minimal handler can be built with a template like this:
```handlebars
Oh no, this program crashed!
{{style "red" error}}
{{*set multi=(gt (len sources) 1)}}
{{#each sources}}
{{#if @first}}
{{~style "dim" "Caused by:"}}
{{/if}}
{{~indent (_if @root.multi @index null) (style "yellow" this)}}
{{/each}}
{{style "cyan" "Please report this issue to ..."}}
```
and you get a flavored error report:
## Additional helpers
### `style` helper
Color the output. Styles should be written at its "dotted" form.
See [console's document](https://docs.rs/console/latest/console/struct.Style.html#implementations) for details.
E.g., `{{style "black.bold.on_red" error}}`
### `indent` helper
Indent a block.
This helper has three forms:
- `indent content` - Indent the content by four spaces.
- `indent <number> content` - Insert a number before the first line with the same indentation level as backtraces.
- `indent <string> content` - Insert given string before every line.
E.g., `{{indent @index this}}`
### inline `_if` helper
Inline version of `if` helper.
E.g., `{{_if success "Yay!" "Oops!"}}`
### `set` decorator
Set local variables.
E.g., `{{*set flag=true}}`
### `concat` helper
Concatenate strings.
E.g., `{{concat "a" "b"}}`
## License
This project is licensed under [MIT License](LICENSE.txt).
