compose-idents 0.3.0

A Rust macro for generating new identifiers (names of variables, functions, traits, etc) by concatenating one or more arbitrary parts and applying other manipulations.
Documentation 
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//! Provides [`Terminated`] type for parsing tokens until a terminator.

use crate::util::log::debug;
use proc_macro2::{TokenStream, TokenTree};
use quote::ToTokens;
use std::marker::PhantomData;
use syn::parse::{Parse, ParseStream};

/// Wraps the token-type `T` and parses it by consuming the input until the terminator `Term` or
/// the end if the input.
pub struct Terminated<T, Term>
where
    T: Parse,
    Term: Parse,
{
    value: T,
    terminator_type: PhantomData<Term>,
}

impl<T, Term> Terminated<T, Term>
where
    T: Parse,
    Term: Parse,
{
    pub(crate) fn into_value(self) -> T {
        self.value
    }
}

impl<T, Term> Parse for Terminated<T, Term>
where
    T: Parse,
    Term: Parse,
{
    fn parse(input: ParseStream) -> syn::Result<Self> {
        let mut tokens = TokenStream::new();
        while !input.is_empty() {
            debug!(
                "Parsing Terminated<{}, {}>: {:?}...",
                std::any::type_name::<T>(),
                std::any::type_name::<Term>(),
                input
            );
            let fork = input.fork();
            let is_terminator = fork.parse::<Term>().is_ok();
            if is_terminator {
                break;
            }
            let tt = input.parse::<TokenTree>()?;
            tokens.extend(tt.into_token_stream());
        }
        debug!(
            "Collecting tokens for Terminated<{}, {}> is successful: {:?}",
            std::any::type_name::<T>(),
            std::any::type_name::<Term>(),
            tokens
        );

        debug!("Parsing {}: {:?}...", std::any::type_name::<T>(), tokens);

        let value = syn::parse2::<T>(tokens)?;

        debug!("Parsing {} is successful.", std::any::type_name::<T>());

        Ok(Terminated {
            value,
            terminator_type: PhantomData,
        })
    }
}