Crate amplify_syn
source ·Expand description
Amplifying Rust language capabilities: helper functions for creating proc macro libraries
Examples
#[name]
- single form
#[name = "literal"]
- optional single value
#[name = TypeName]
- path value
#[name("literal", TypeName, arg = value)]
- list of arguments
Macros
Convenience macro for constructing
syn::Ident
from literalsStructs
Structure requirements for parametrized attribute
Drop-in replacement for
syn::NestedMeta
, which allows to parse
attributes which can have arguments made of either literal, path or
MetaArgNameValue
expressions.Drop-in replacement for
syn::MetaNameValue
used for parsing named
arguments inside attributes which name is always an proc_macro2::Ident
(and not syn::Path
) and value can be not only a literal, but of any
valid rust type.Representation for all allowed forms of
#[attr(...)]
attribute.
If attribute has a multiple occurrences they are all assembled into a single
list. Repeated named arguments are not allowed and result in errors.Structure describing a procedural macro attribute with an optional value.
The means that if one has something like
#[name1]
, #[name2 = "value"]
,
#[name3 = ::std::path::PathBuf)]
than name1
, name2 = "value"
, and
name3 = ::std::path::PathBuf
are three different attributes which can be
parsed and represented by the SingularAttr
structure.Enums
Value for attribute or attribute argument, i.e. for
#[attr = value]
and
#[attr(arg = value)]
this is the value
part of the attribute. Can be
either a single literal or a single valid rust type nameRequirements for attribute or named argument value presence
Internal structure representation of a proc macro attribute collected
instances having some specific name (accessible via
Attr::name()
).Errors representing inconsistency in proc macro attribute structure
Requirements for list elements. For instance, used in
AttrReq
for
providing crate::ParametrizedAttr
fields requirements.Constrains for literal value type
Drop-in replacement for
syn::NestedMeta
, which allows to parse
attributes which can have arguments made of either literal, path or
MetaArgNameValue
expressions.Constrains for the possible types that a Rust value could have.
Constrains for attribute value type
Requirements for attribute or named argument value presence for a values
with known class. If the value class is not known, use
ArgValueReq
instead.