method_chaining 0.1.1

A Rust procedural macro that automatically makes functions and structs chainable.
Documentation 
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use proc_macro::TokenStream;
use quote::quote;
use syn::{parse_macro_input, ItemStruct, Meta};

pub fn make_struct_chainable(_attr: TokenStream, item: TokenStream) -> TokenStream {
    let input_struct = parse_macro_input!(item as ItemStruct);

    // 检查是否有 chain_push 或 chain_insert 属性
    for attr in &input_struct.attrs {
        match &attr.meta {
            Meta::List(list) if list.path.is_ident("chain_push") => {
                // 这些属性会由单独的宏处理
                continue;
            }
            Meta::List(list) if list.path.is_ident("chain_insert") => {
                // 这些属性会由单独的宏处理
                continue;
            }
            _ => {}
        }
    }

    // Generate the chainable methods for each field
    let methods: Vec<_> = input_struct
        .fields
        .iter()
        .map(|field| {
            let function_name = syn::Ident::new(
                &format!("with_{}", field.ident.as_ref().unwrap()),
                field.ident.as_ref().unwrap().span(),
            );
            let field_name = &field.ident;
            let field_type = &field.ty;

            quote! {
                pub fn #function_name(mut self, value: #field_type) -> Self {
                    self.#field_name = value;
                    self
                }
            }
        })
        .collect();

    let name = &input_struct.ident;

    let result = quote! {
        #input_struct

        impl #name {
            #(#methods)*
        }
    };

    result.into()
}