Crate proc_easy

Making proc-macro easy.

Modules

examples

Macros

easy_argument

Defines argument structure. First field is a argument name. It must be EasyToken implementation that will be used to for EasyPeek implementation. And following fields are parsed in order. In case of errors, argument name and span will be used.

easy_argument_group

Defines argument group as enum where each variant is argument type.

easy_argument_tuple

Defines argument structure. First field is a argument name. It must be EasyToken implementation that will be used to for EasyPeek implementation. Following fields must be EasyArgumentField and are expected to be in parenthesized and parsed in any order. If name is not followed by parentheses, all fields are missing. In case of errors, argument name and span will be used.

easy_argument_value

Defines argument structure of two fields. First field is a argument name. It must be EasyToken implementation that will be used to for EasyPeek implementation. Second field must be EasyArgumentField and is expected to follow = token. If name is not followed by =, second field is missing. In case of errors, argument name and span will be used.

easy_attributes

Defines struct and implement EasyAttributes for it. Each field’s type must implement EasyArgumentField.

easy_flags

Defines flags and attribute group and fields for them. Flags can be parsed independently. They can be parsed inside attribute that can contain only one flag. They can be parsed inside attribute that accepts a list of flags if provided.

easy_parse

Defines structure or enum and implements Parse for it

easy_separated

Defines structure and implements Parse for it.

easy_terminated

Defines structure and implements Parse for it.

easy_token

Produces type with specified name that implement EasyToken and can be parsed from the name ident.

Structs

EasyBraced

Parses inner type braced. Implements EasyPeek and peeks opening brace.

EasyBracketed

Parses inner type bracketed. Implements EasyPeek and peeks opening bracket.

EasyParenthesized

Parses inner type parenthesized. Implements EasyPeek and peeks opening parenthesis.

EasySeparated

Similar to syn::punctuated::Punctuated that implements Parse and possibly EasyPeek. Parses one or more occurrences of T separated by punctuation of type P, not accepting trailing punctuation. Parsing continues as long as punctuation P is present at the head of the stream. This method returns upon parsing a T and observing that it is not followed by a P, even if there are remaining tokens in the stream.

EasyTerminated

Similar to syn::punctuated::Punctuated that implements Parse. Parses zero or more occurrences of T separated by punctuation of type P, with optional trailing punctuation. Parsing continues until the end of this parse stream. The entire content of this parse stream must consist of T and P.

Enums

EasyMaybe

Similar to Option but implements Parse when T implements EasyPeek If stream doesn’t start with as T, it is parsed without consuming any tokens and parse result is [Nothing]. Otherwise T is parsed and wrapped in [Just]

EasySubArgument

Either value preceded by = or tuple sub-fields.

ReferenceExpr

Expression that may be a constant or a reference to member field. Often used pattern is having attribute that refer to a field or constant expression.

Traits

EasyArgument

Trait for parsable attributes. Attributes should be peekable to choose which attribute to parse.

EasyArgumentField

Trait for types that can be used as fields in easy attributes structures. Fields can parsed and extended when encountered again in parsing stream. If field is never encountered - [missing] value will be used. If attribute type or group is not mandatory - wrap it into Option.

EasyArgumentGroup

Trait that should be implemented for enums of where each variant is an attribute. It is also auto-implemented for all bare attributes. This trait is used to implement EasyArgumentField for various types.

EasyAttributes

Collection of attributes that can be parsed from array of attributes. Can be easily applied to field’s or type’s attributes vector.

EasyPeek

Provides interface for peeking tokens before parsing. When implemented for complex structures, peeks first token.

EasyToken

Peekable, parsable token.