* Fine tune whitespace
The EEx outut now emits more human-readable and predictable formatting.
This includes proper indenting, at least for each "root" template.
* Internal whitespace control
You can now use a bang version of any nonvoid tag to emit the markup
witout the internal whitespace. This means that there will not be a
newline emitted after the opening tag and before the closing tag.
Before this change, only keyword list literals could be passed to
elements. If they had non-literals as values, then those would compile
to EEx expressions.
This allows a non-literal to be passed as attrs and have the entire thing
compile to an EEx expression, which will pass the non-literal to a
"runtime_attrs" function, which evaluates a keyword list into a safe
string.
That last part might need to be reworked if the user is not using
the Phoenix.HTML.Engine EEx Engine.
Components work very similarly to how they worked before, but with a few
differences.
To define a component, you can create a file in your configured temple
components directory, which defaults to `lib/components`. You would
probably want ot change that to be `lib/my_app_web/components` if you
are building a phoenix app.
This file should be of the `.exs` extension, and contain any temple
compatible code.
You can then use this component in any other temple template.
For example, if I were to define a `flex` component, I would create a
file called `lib/my_app_web/components/flex.exs`, with the following
contents.
```elixir
div class: "flex #{@temple[:class]}", id: @id do
@children
end
```
And we could use the component like so
```elixir
flex class: "justify-between items-center", id: "arnold" do
div do: "Hi"
div do: "I'm"
div do: "Arnold"
div do: "Schwarzenegger"
end
```
We've demonstated several features to components in this example.
We can pass assigns to our component, and access them just like we would
in a normal phoenix template. If they don't match up with any assigns we
passed to our component, they will be rendered as-is, and will become a
normal Phoenix assign.
You can also access a special `@temple` assign. This allows you do
optionally pass an assign, and not have the `@my_assign` pass through.
If you didn't pass it to your component, it will evaluate to nil.
The block passed to your component can be accessed as `@children`. This
allows your components to wrap a body of markup from the call site.
In order for components to trigger a recompile when they are changed,
you can call `use Temple.Recompiler` in your `lib/my_app_web.ex` file,
in the `view`, `live_view`, and `live_component` functions
```elixir
def view do
quote do
# ...
use Temple.Recompiler
# ...
end
end
```
Recursively calling the macros works fine if you `import` the whole
module wherever you are using your components, but not if you `require`
the module.
This is because importing brings in the all the macros into the callers
namespace, which allows them to be called just by the macro name. When
you `require` the module, it will look for the generated 2-arity macro
in the callers namespace, which probably doesn't exist.
We get around this by not recursively calling them and avoiding the
problem all togther. A few utility functions solves the original issue
of wanting to DRY the file.
