CRSN Sexp
=========

This is an updated and extended version of the "sexp" crate by Clark Gaebel: [https://github.com/cgaebel/sexp](https://github.com/cgaebel/sexp).

## Changes from "cgaebel/sexp"

- Updated to the 2018 Rust edition (that is, removed `try!()` and such)
- All parsed atoms now track their source location. This enables better error reporting in subsequent parsing and processing.
- Quoted strings now support C-style escapes other than `\"`, such as `\n`, `\t` and `\\`. 
  - Unrecognized escapes result in the slash being removed and the next character being taken literally. Use `\\` to enter a backslash.
- Added special parsing of "character literals" that use single quotes (`'A'`) and may contain backslash escapes (`'\n'`).
  - This does not interfere with "apostrophe tokens" like `'foo`, that becomes an unquoted string atom.
- Added "quoted string", "unsigned" and "character" atom types
- Added parsing for `0x123`, `#ff00ff` and `0b123456`
- Numeric literals may now contain underscores to separate digit groups
- Numbers are preferably parsed as the unsigned atom (u64). The signed atom (i64) is only used for negative numbers.

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