Enum Attribute

pub enum Attribute {
    Marker(Ident),
    List(MetaList),
    KeyValue(MetaKeyValue),
}

An Attribute represents some named metadata attached to a Miden Assembly procedure.

An attribute has no predefined structure per se, but syntactically there are three types:

• Marker attributes, i.e. just a name and no associated data. Attributes of this type are used to “mark” the item they are attached to with some unique trait or behavior implied by the name. For example, @inline. NOTE: @inline() is not valid syntax.

• List attributes, i.e. a name and one or more comma-delimited expressions. Attributes of this type are used for cases where you want to parameterize a marker-like trait. To use a Rust example, #[derive(Trait)] is a list attribute, where derive is the marker, but we want to instruct whatever processes derives, what traits it needs to derive. The equivalent syntax in Miden Assembly would be @derive(Trait). Lists must always have at least one item.

• Key-value attributes, i.e. a name and a value. Attributes of this type are used to attach named properties to an item. For example, @storage(offset = 1). Possible value types are: bare identifiers, decimal or hexadecimal integers, and quoted strings.

There are no restrictions on what attributes can exist or be used. However, there are a set of attributes that the assembler knows about, and acts on, which will be stripped during assembly. Any remaining attributes we don’t explicitly handle in the assembler, will be passed along as metadata attached to the procedures in the MAST output by the assembler.

Variants

Marker(Ident)

A named behavior, trait or action; e.g. @inline

List(MetaList)

A parameterized behavior, trait or action; e.g. @inline(always) or @derive(Foo, Bar)

KeyValue(MetaKeyValue)

A named property; e.g. @props(key = "value"), @props(a = 1, b = 0x1)

Implementations

impl Attribute

pub fn new(name: Ident, metadata: impl Into<Meta>) -> Attribute

Create a new Attribute with the given metadata.

The metadata value must be convertible to Meta.

For marker attributes, you can either construct the Marker variant directly, or pass either Meta::Unit or None as the metadata argument.

If the metadata is empty, a Marker attribute will be produced, otherwise the type depends on the metadata. If the metadata is not key-value shaped, a List is produced, otherwise a KeyValue.

pub fn from_iter<V, I>(name: Ident, metadata: I) -> Attribute

where Meta: FromIterator<V>, I: IntoIterator<Item = V>,

Create a new Attribute from an metadata-producing iterator.

If the iterator is empty, a Marker attribute will be produced, otherwise the type depends on the metadata. If the metadata is not key-value shaped, a List is produced, otherwise a KeyValue.

pub fn with_span(self, span: SourceSpan) -> Attribute

Set the source location for this attribute

pub fn name(&self) -> &str

Get the name of this attribute as a string

pub fn id(&self) -> Ident

Get the name of this attribute as an Ident

pub fn is_marker(&self) -> bool

Returns true if this is a marker attribute

pub fn is_list(&self) -> bool

Returns true if this is a list attribute

pub fn is_key_value(&self) -> bool

Returns true if this is a key-value attribute

pub fn metadata(&self) -> Option<BorrowedMeta<'_>>

Get the metadata for this attribute

Returns None if this is a marker attribute, and thus has no metadata

Trait Implementations

impl Clone for Attribute

fn clone(&self) -> Attribute

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Attribute

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl Display for Attribute

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl Extend<Attribute> for AttributeSet

fn extend<T>(&mut self, iter: T)

where T: IntoIterator<Item = Attribute>,

Extends a collection with the contents of an iterator.

fn extend_one(&mut self, item: A)

🔬This is a nightly-only experimental API. (extend_one)

Extends a collection with exactly one element.

fn extend_reserve(&mut self, additional: usize)

🔬This is a nightly-only experimental API. (extend_one)

Reserves capacity in a collection for the given number of additional elements.

impl<K, V> From<(K, V)> for Attribute

where K: Into<Ident>, V: Into<MetaExpr>,

fn from(kv: (K, V)) -> Attribute

Converts to this type from the input type.

impl From<Ident> for Attribute

fn from(value: Ident) -> Attribute

Converts to this type from the input type.

impl From<MetaKeyValue> for Attribute

fn from(value: MetaKeyValue) -> Attribute

Converts to this type from the input type.

impl From<MetaList> for Attribute

fn from(value: MetaList) -> Attribute

Converts to this type from the input type.

impl FromIterator<Attribute> for AttributeSet

fn from_iter<T>(iter: T) -> AttributeSet

where T: IntoIterator<Item = Attribute>,

Creates a value from an iterator.

impl Hash for Attribute

fn hash<__H>(&self, state: &mut __H)

where __H: Hasher,

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl Ord for Attribute

fn cmp(&self, other: &Attribute) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

impl PartialEq for Attribute

fn eq(&self, other: &Attribute) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl PartialOrd for Attribute

fn partial_cmp(&self, other: &Attribute) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl PrettyPrint for Attribute

fn render(&self) -> Document

The core of the PrettyPrint functionality.

fn to_pretty_string(&self) -> String

Produce a String containing the results of pretty-printing this object.

fn pretty_print(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Pretty-print this object to the given core::fmt::Formatter.

impl Spanned for Attribute

fn span(&self) -> SourceSpan

impl Eq for Attribute

impl StructuralPartialEq for Attribute