Crate proclet

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§proclet: proc macros made easy

⚠️ proclet is still in early development. It’s missing some basic features and may get major design changes, and documentation is a work in progress.

proclet can be used with either proc-macro or proc-macro2, or both. Most of the types of the proc-macro crates are abstracted into traits, and proclet’s types are generic over these traits. If you run into type inference issues, there’s proc-macro specific aliases for the proclet types in the pm1 and pm2 modules.

Here’s how you’d make a proc macro that takes a set of comma separated strings as arguments (last comma optional):

#[proc_macro]
pub fn my_proc_macro(input: TokenStream) -> TokenStream {
    proclet(input, |input| {
        let args = punctuated(StringLiteral::parser(), op(",")).parse_all(input)?;
        // ...
    })
}

The proclet function is an optional wrapper that converts the input to a TokenBuf ready for parsing, converts the output back into a TokenStream, and handles errors by making them nice spanned compiler errors instead of panics.

parse_all returns an error if there’s tokens left in the buffer after parsing. To leave the rest of the buffer for the next parser to parse, use the parse method instead.

You can combine parsers to parse more complex objects like punctuated does in the example above. Types that implement the Parse trait can be parsed directly:

let string = StringLiteral::parse(input)?;

The input is automatically advanced to point past the parsed object on success.

Modules§

  • pm1proc-macro
    Type aliases for use with proc-macro.
  • pm2proc-macro2
    Type aliases for use with proc-macro2.
  • prelude
    The prelude imports all the crate’s traits with use ... as _.

Structs§

  • ByteCharacterLiteralliteral-value
    A byte character literal. This can be converted to and from LiteralValue.
  • ByteStringLiteralliteral-value
    A byte string literal. This can be converted to and from LiteralValue.
  • CharacterLiteralliteral-value
    A character literal. This can be converted to and from LiteralValue.
  • Error
    An error.
  • F32Literalliteral-value
    f32 suffixed floating point literal. This can be converted to and from LiteralValue.
  • F64Literalliteral-value
    f64 suffixed floating point literal. This can be converted to and from LiteralValue.
  • FloatLiteralliteral-value
    Unsuffixed floating point literal. This can be converted to and from LiteralValue.
  • I8Literalliteral-value
    i8 suffixed integer literal. This can be converted to and from LiteralValue.
  • I16Literalliteral-value
    i16 suffixed integer literal. This can be converted to and from LiteralValue.
  • I32Literalliteral-value
    i32 suffixed integer literal. This can be converted to and from LiteralValue.
  • I64Literalliteral-value
    i64 suffixed integer literal. This can be converted to and from LiteralValue.
  • I128Literalliteral-value
    i128 suffixed integer literal. This can be converted to and from LiteralValue.
  • IntLiteralliteral-value
    Unsuffixed integer literal. This can be converted to and from LiteralValue.
  • IsizeLiteralliteral-value
    isize suffixed integer literal. This can be converted to and from LiteralValue.
  • Op
    An operator. These can be parsed from tokens, and can also be used as parsers to parse one specific operator.
  • OpParser
    Parser for specific sets of operators. Ops can be parsed via Parser or manually from Puncts.
  • OpParserInstance
    An instance for doing manual parsing of operators.
  • Optional
    Wrap a parser in this to make it always succeed and return an Option.
  • PM1proc-macro
    Marker type for the proc-macro crate.
  • PM2proc-macro2
    Marker type for the proc-macro2 crate.
  • Puncts
    Iterator over Puncts.
  • Punctuated
    Parsed punctuated values.
  • PunctuatedParser
    Parser for punctuated values.
  • StringLiteralliteral-value
    A string literal. This can be converted to and from LiteralValue.
  • TokenBuf
    Borrowed version of TokenBuffer.
  • TokenBuffer
    An owned buffer of tokens.
  • U8Literalliteral-value
    u8 suffixed integer literal. This can be converted to and from LiteralValue.
  • U16Literalliteral-value
    u16 suffixed integer literal. This can be converted to and from LiteralValue.
  • U32Literalliteral-value
    u32 suffixed integer literal. This can be converted to and from LiteralValue.
  • U64Literalliteral-value
    u64 suffixed integer literal. This can be converted to and from LiteralValue.
  • U128Literalliteral-value
    u128 suffixed integer literal. This can be converted to and from LiteralValue.
  • UsizeLiteralliteral-value
    usize suffixed integer literal. This can be converted to and from LiteralValue.

Enums§

  • DelimiterKind
    Delimiter. This is exactly like proc_macro*::Delimiter, but doesn’t depend on which proc-macro crate you use.
  • LiteralValueliteral-value
    A literal token. This is like Literal from proc-macro*, except that the value has already been parsed and is available at no cost. You can convert it to and from Literal with into.
  • Match
    Match results.
  • TokenTreeKind
    The kind of a TokenTree. This is like the enum in proc_macro*::TokenTree, but without any contained data. It doesn’t depend on which proc-macro crate you use.

Traits§

Functions§