literalext

WARNING: This crate is no longer maintained. The literal parsing logic in this crate has been moved into syn 0.12.

To get similar behaviour with syn, parse a syn::Lit by calling syn::parse2::<syn::Lit>(ts) or syn::parse_str::<syn::Lit>(s).

This crate provides extension methods to proc-macro, and proc-macro2's Literal types. These methods provide a mechanism for extracting the value of the type.

API

Adds a trait with implementations for the types proc_macro2::Literal, proc_macro::Literal, and DummyLiteral with the following methods for extracting the value of the type:

pub trait LiteralExt {
    /// If the `Literal` is an integer literal, returns its value.
    fn parse_int(&self) -> Option<IntLit>;

    /// If the `Literal` is a floating point literal, returns its value.
    fn parse_float(&self) -> Option<FloatLit>;

    /// If the `Literal` is a string literal, returns it's value.
    fn parse_string(&self) -> Option<String>;

    /// If the `Literal` is a char literal, returns it's value.
    fn parse_char(&self) -> Option<char>;

    /// If the `Literal` is a byte string literal, returns it's value.
    fn parse_bytes(&self) -> Option<Vec<u8>>;

    /// If the `Literal` is a byte literal, returns it's value.
    fn parse_byte(&self) -> Option<u8>;

    /// If the `Literal` is an inner doc comment (`//!` or `/*!`), returns a
    /// string with the text of the comment.
    fn parse_inner_doc(&self) -> Option<String>;

    /// If the `Literal` is an outer doc comment (`///` or `/**`), returns a
    /// string with the text of the comment.
    fn parse_outer_doc(&self) -> Option<String>;
}

Supported Features

• i128: Add support for interpreting the i128 and u128 integer types. nightly only

• proc-macro2 default: Implement LiteralExt on proc_macro2::Literal.

• proc-macro: Implement LiteralExt on proc_macro::Literal. nightly only

• dummy: Export a type DummyLiteral with a public constructor which implements the LiteralExt trait.