diff options
Diffstat (limited to 'mingling_macros/src/lib.rs')
| -rw-r--r-- | mingling_macros/src/lib.rs | 191 |
1 files changed, 191 insertions, 0 deletions
diff --git a/mingling_macros/src/lib.rs b/mingling_macros/src/lib.rs index 56ed999..ca3261e 100644 --- a/mingling_macros/src/lib.rs +++ b/mingling_macros/src/lib.rs @@ -590,6 +590,56 @@ pub fn route(input: TokenStream) -> TokenStream { TokenStream::from(expanded) } +/// Routes errors to the rendering pipeline instead of the chain pipeline. +/// +/// This macro is similar to [`route!`] but instead of routing errors through +/// `Routable::to_chain()` (which returns `ChainProcess`), it routes them +/// directly to the renderer via `crate::ThisProgram::render(AnyOutput::new(e))` +/// (which returns `RenderResult`). +/// +/// This is useful in `#[renderer]` and `#[help]` functions where the return +/// type is `RenderResult` rather than `ChainProcess`. +/// +/// # Syntax +/// +/// ```rust,ignore +/// render_route!(expr) +/// ``` +/// +/// Where `expr` is an expression of type `Result<T, E>`. +/// +/// # Interaction with `#[routeify]` +/// +/// When `#[routeify]` is used on a `#[renderer]` or `#[help]` function (e.g. +/// `#[renderer(routeify)]` or `#[help(routeify)]`), every `expr?` is automatically +/// replaced with `render_route!(expr)` instead of `route!(expr)`. +/// +/// # Example +/// +/// ```rust,ignore +/// use mingling::macros::{renderer, render_route}; +/// use std::io::Write; +/// +/// #[renderer] +/// fn render_something(prev: SomeType) -> RenderResult { +/// let data = render_route!(fetch_data().map_err(|e| ErrorEntry::new(e.to_string())))?; +/// // ... render data +/// Ok(RenderResult::new()) +/// } +/// ``` +#[cfg(feature = "extra_macros")] +#[proc_macro] +pub fn render_route(input: TokenStream) -> TokenStream { + let expr = parse_macro_input!(input as syn::Expr); + let expanded = quote! { + match #expr { + Ok(r) => r, + Err(e) => return <crate::ThisProgram as ::mingling::ProgramCollect>::render(::mingling::AnyOutput::new(e)), + } + }; + TokenStream::from(expanded) +} + /// Creates an empty result value wrapped in `ChainProcess` for early return /// from a chain function. /// @@ -1293,6 +1343,25 @@ pub fn help(attr: TokenStream, item: TokenStream) -> TokenStream { help::help_attr(item) } +/// Marker attribute for the Mingling lint system. +/// +/// The content of this attribute is ignored by rustc and reserved for +/// the mlint tool to interpret. All it does is pass the item through +/// unchanged. +/// +/// # Examples +/// +/// ```rust,ignore +/// #[mlint(allow(MLINT_SOME_LINT))] +/// #[mlint(warn(MLINT_SOME_LINT))] +/// #[mlint(deny(MLINT_SOME_LINT))] +/// fn some_item() {} +/// ``` +#[proc_macro_attribute] +pub fn mlint(_attr: TokenStream, item: TokenStream) -> TokenStream { + item +} + /// Extension attribute macro that transforms `expr?` into `route!(expr)`. /// /// Designed for use with `#[chain(routeify, ...)]` to enable concise error @@ -1314,6 +1383,32 @@ pub fn routeify(attr: TokenStream, item: TokenStream) -> TokenStream { extensions::routeify::routeify_impl(attr, item) } +/// Extension attribute macro that transforms `expr?` into `render_route!(expr)`. +/// +/// Designed for use with `#[renderer(renderify, ...)]` or `#[help(renderify, ...)]` +/// to enable concise error routing in renderer and help functions using the `?` +/// operator syntax. +/// +/// Unlike `#[routeify]` which routes errors to the chain pipeline via `route!`, +/// `#[renderify]` routes errors to the rendering pipeline via `render_route!`, +/// which matches the `RenderResult` return type of renderer and help functions. +/// +/// # Example +/// +/// ```rust,ignore +/// #[renderer(renderify)] +/// fn render_greeting(prev: Greeting) -> RenderResult { +/// let data = load_data()?; // expands to render_route!(load_data()) +/// r_println!("{data}"); +/// Ok(RenderResult::new()) +/// } +/// ``` +#[cfg(feature = "extra_macros")] +#[proc_macro_attribute] +pub fn renderify(attr: TokenStream, item: TokenStream) -> TokenStream { + extensions::renderify::renderify_impl(attr, item) +} + /// Wraps a unit-returning function to produce a `RenderResult`. /// /// The `#[buffer]` attribute macro injects a local `__render_result_buffer` @@ -1412,6 +1507,102 @@ pub fn r_print(input: TokenStream) -> TokenStream { func::r_print::r_print(input) } +/// Prints text to a `RenderResult` buffer (standard error style), with a trailing newline. +/// +/// This macro works identically to `r_println!` but conceptually targets +/// "error output" — it writes into a `RenderResult` buffer with a trailing newline. +/// +/// # Implicit buffer (inside `#[buffer]` functions) +/// +/// ```rust,ignore +/// use mingling::macros::{buffer, r_eprintln}; +/// +/// #[buffer] +/// fn render() { +/// r_eprintln!("Error: {}", err_msg); +/// } +/// ``` +/// +/// # Explicit buffer +/// +/// Pass a `RenderResult` variable as the first argument: +/// +/// ```rust,ignore +/// use mingling::macros::r_eprintln; +/// use mingling::RenderResult; +/// +/// let mut r = RenderResult::new(); +/// r_eprintln!(r, "error: {}", 42); +/// assert_eq!(&*r, "error: 42\n"); +/// ``` +#[proc_macro] +pub fn r_eprintln(input: TokenStream) -> TokenStream { + func::r_print::r_eprintln(input) +} + +/// Prints text to a `RenderResult` buffer (standard error style), without a trailing newline. +/// +/// This macro works identically to `r_print!` but conceptually targets +/// "error output" — it writes into a `RenderResult` buffer without a trailing newline. +/// +/// # Implicit buffer (inside `#[buffer]` functions) +/// +/// ```rust,ignore +/// use mingling::macros::{buffer, r_eprint}; +/// +/// #[buffer] +/// fn render() { +/// r_eprint!("Error: "); +/// r_eprintln!("something went wrong"); +/// } +/// ``` +/// +/// # Explicit buffer +/// +/// ```rust,ignore +/// use mingling::macros::r_eprint; +/// use mingling::RenderResult; +/// +/// let mut r = RenderResult::new(); +/// r_eprint!(r, "error: "); +/// r_eprintln!(r, "42"); +/// assert_eq!(&*r, "error: 42\n"); +/// ``` +#[proc_macro] +pub fn r_eprint(input: TokenStream) -> TokenStream { + func::r_print::r_eprint(input) +} + +/// Appends the contents of one `RenderResult` to another. +/// +/// # Implicit buffer (inside `#[buffer]` functions) +/// +/// ```rust,ignore +/// use mingling::macros::{buffer, r_append}; +/// +/// #[buffer] +/// fn render() { +/// let other = make_other_result(); +/// r_append!(other); +/// } +/// ``` +/// +/// # Explicit buffer +/// +/// ```rust,ignore +/// use mingling::macros::r_append; +/// use mingling::RenderResult; +/// +/// let mut dst = RenderResult::new(); +/// let src = RenderResult::from("hello"); +/// r_append!(dst, src); +/// assert!(!dst.is_empty()); +/// ``` +#[proc_macro] +pub fn r_append(input: TokenStream) -> TokenStream { + func::r_print::r_append(input) +} + /// Derive macro for automatically implementing the `Grouped` trait on a struct. /// /// The `#[derive(Grouped)]` macro: |