memtable-macros 0.2.0

Macro library that provides ability to derive typed tables and generate tables compile-time.
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use super::{utils, TableColumn, TableMode};
use syn::{parse_quote, Generics, Ident, ItemFn, Path};

pub struct Args<'a> {
    pub root: &'a Path,
    pub mode: TableMode,
    pub generics: &'a Generics,
    pub table_data_name: &'a Ident,
    pub columns: &'a [&'a TableColumn],
}

pub fn make(args: Args) -> ItemFn {
    let Args {
        root,
        mode,
        generics,
        table_data_name,
        columns,
    } = args;

    let (_, ty_generics, _) = generics.split_for_impl();
    let column_names = utils::make_column_names(columns, ToString::to_string);
    let idx = utils::make_column_indexes(columns);
    let inner_table_ty =
        utils::make_inner_table_type(root, mode, table_data_name, generics, columns.len());

    parse_quote! {
        /// Converts into a column by its name
        pub fn into_column_by_name(
            self,
            name: &::core::primitive::str,
        ) -> ::core::option::Option<#root::iter::IntoColumn<
            #table_data_name #ty_generics,
            #inner_table_ty,
        >> {
            match name {
                #(
                    #column_names => ::core::option::Option::Some(
                        #root::Table::into_column(self.0, #idx)
                    ),
                )*
                _ => ::core::option::Option::None,
            }
        }
    }
}