bendns' repos / helix
Unnamed repository; edit this file 'description' to name the repository.
Diffstat (limited to 'helix-config/src/macros.rs')
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+/// This macro allows specifiying a trait of related config
+/// options with a struct like syntax. From that information
+/// two things are generated:
+///
+/// * A `init_config` function that registers the config options with the
+/// `OptionRegistry` registry.
+/// * A **trait** definition with an accessor for every config option that is
+/// implemented for `OptionManager`.
+///
+/// The accessors on the trait allow convenient statically typed access to
+/// config fields. The accessors return `Guard<T>` (which allows derferecning to
+/// &T). Any type that implements copy can be returned as a copy instead by
+/// specifying `#[read = copy]`. Collections like `List<T>` and `String` are not
+/// copy However, they usually implement deref (to &[T] and &str respectively).
+/// Working with the dereferneced &str/&[T] is more convenient then &String and &List<T>. The
+/// accessor will return these if `#[read = deref]` is specified.
+///
+/// The doc comments will be retained for the accessors and also stored in the
+/// option registrry for dispaly in the UI and documentation.
+///
+/// The name of a config option can be changed with #[name = "<name>"],
+/// otherwise the name of the field is used directly. The OptionRegistry
+/// automatically converts all names to kebab-case so a name attribute is only
+/// required if the name is supposed to be significantly altered.
+///
+/// In some cases more complex validation may be necssary. In that case the
+/// valiidtator can be provided with an exprission that implements the `Validator`
+/// trait: `#[validator = create_validator()]`.
+#[macro_export]
+macro_rules! options {
+ (
+ $(use $use: ident::*;)*
+ $($(#[$($meta: tt)*])* struct $ident: ident {
+ $(
+ $(#[doc = $option_desc: literal])*
+ $(#[name = $option_name: literal])?
+ $(#[validator = $option_validator: expr])?
+ $(#[read = $($extra: tt)*])?
+ $option: ident: $ty: ty = $default: expr
+ ),+$(,)?
+ })+
+ ) => {
+ $(pub use $use::*;)*
+ $($(#[$($meta)*])* pub trait $ident {
+ $(
+ $(#[doc = $option_desc])*
+ fn $option(&self) -> $crate::options!(@ret_ty $($($extra)*)? $ty);
+ )+
+ })+
+ pub fn init_config(registry: &mut $crate::OptionRegistry) {
+ $($use::init_config(registry);)*
+ $($(
+ let name = $crate::options!(@name $option $($option_name)?);
+ let docs = concat!("" $(,$option_desc,)" "*);
+ $crate::options!(@register registry name docs $default, $ty $(,$option_validator)?);
+ )+)+
+ }
+ $(impl $ident for $crate::OptionManager {
+ $(
+ $(#[doc = $option_desc])*
+ fn $option(&self) -> $crate::options!(@ret_ty $($($extra)*)? $ty) {
+ let name = $crate::options!(@name $option $($option_name)?);
+ $crate::options!(@get $($($extra)*)? self, $ty, name)
+ }
+ )+
+ })+
+ };
+ (@register $registry: ident $name: ident $desc: ident $default: expr, $ty:ty) => {{
+ use $crate::IntoTy;
+ let val: $ty = $default.into_ty();
+ $registry.register($name, $desc, val);
+ }};
+ (@register $registry: ident $name: ident $desc: ident $default: expr, $ty:ty, $validator: expr) => {{
+ use $crate::IntoTy;
+ let val: $ty = $default.into_ty();
+ $registry.register_with_validator($name, $desc, val, $validator);
+ }};
+ (@name $ident: ident) => {
+ ::std::stringify!($ident)
+ };
+ (@name $ident: ident $name: literal) => {
+ $name
+ };
+ (@ret_ty copy $ty: ty) => {
+ $ty
+ };
+ (@ret_ty map($fn: expr, $ret_ty: ty) $ty: ty) => {
+ $ret_ty
+ };
+ (@ret_ty fold($init: expr, $fn: expr, $ret_ty: ty) $ty: ty) => {
+ $ret_ty
+ };
+ (@ret_ty deref $ty: ty) => {
+ $crate::Guard<'_, <$ty as ::std::ops::Deref>::Target>
+ };
+ (@ret_ty $ty: ty) => {
+ $crate::Guard<'_, $ty>
+ };
+ (@get map($fn: expr, $ret_ty: ty) $config: ident, $ty: ty, $name: ident) => {
+ let val = $config.get::<$ty>($name);
+ $fn(val)
+ };
+ (@get fold($init: expr, $fn: expr, $ret_ty: ty) $config: ident, $ty: ty, $name: ident) => {
+ $config.get_folded::<$ty, $ret_ty>($name, $init, $fn)
+ };
+ (@get copy $config: ident, $ty: ty, $name: ident) => {
+ *$config.get::<$ty>($name)
+ };
+ (@get deref $config: ident, $ty: ty, $name: ident) => {
+ $config.get_deref::<$ty>($name)
+ };
+ (@get $config: ident, $ty: ty, $name: ident) => {
+ $config.get::<$ty>($name)
+ };
+}
+
+#[macro_export]
+macro_rules! config_serde_adapter {
+ ($ty: ident) => {
+ impl $crate::Ty for $ty {
+ fn to_value(&self) -> $crate::Value {
+ $crate::to_value(self).unwrap()
+ }
+ fn from_value(val: $crate::Value) -> ::anyhow::Result<Self> {
+ let val = $crate::from_value(val)?;
+ Ok(val)
+ }
+ }
+ };
+}