Search Results for "error"

Logos is a lexer generator for Rust, designed to create fast and efficient lexers with minimal code. It leverages Rust's procedural macros to define token patterns, streamlining the process of lexical analysis.​

rust-peg is a Parsing Expression Grammar (PEG) parser generator for Rust. It allows developers to define grammars in a concise syntax and generates efficient parsers, facilitating the creation of domain-specific languages and interpreters.​

...The primary target is macro authors: you can parse TokenStreams into syn::File, syn::Item, syn::Expr, syn::Type, etc. It offers rich data structures, fine-grained parsing, span tracking (for error reporting), traversal and mutation APIs (visit, fold, visit_mut), printing back to tokens, and strong feature-gating so you only compile what you need. The documentation emphasises that while the crate is geared for procedural macros (and custom derives), some of the APIs may be of more general use. Using syn you can effectively write code that analyzes or generates Rust code at compile time.

...The API is intentionally compact so you can parse arguments inline near main() and map them straight into native types. It supports short and long options, boolean switches, and key–value flags while keeping error messages and help output understandable for end users. Subcommands can be modeled without much boilerplate, letting you structure larger CLIs while keeping each command self-contained. The overall feel is “get out of your way”: minimal setup, zero magic, and a straightforward path from argv to validated inputs.