Struct scale_info::Field
source · [−]Expand description
A field of a struct-like data type.
Name is optional so it can represent both named and unnamed fields.
This can be a named field of a struct type or an enum struct variant, or an unnamed field of a tuple struct.
Type name
The type_name
field contains a string which is the name of the type of the
field as it appears in the source code. The exact contents and format of the
type name are not specified, but in practice will be the name of any valid
type for a field e.g.
- Concrete types e.g
"u32"
,"bool"
,"Foo"
etc. - Type parameters e.g
"T"
,"U"
- Generic types e.g
"Vec<u32>"
,"Vec<T>"
- Associated types e.g.
"T::MyType"
,"<T as MyTrait>::MyType"
- Type aliases e.g.
"MyTypeAlias"
,"MyTypeAlias<T>"
- Other built in Rust types e.g. arrays, references etc.
Note that the type name doesn’t correspond to the underlying type of the field, unless using a concrete type directly. Any given type may be referred to by multiple field type names, when using generic type parameters and type aliases.
This is intended for informational and diagnostic purposes only. Although it is possible to infer certain properties e.g. whether a type name is a type alias, there are no guarantees provided, and the type name representation may change.
Implementations
sourceimpl Field
impl Field
sourcepub fn builder() -> FieldBuilder
pub fn builder() -> FieldBuilder
Returns a new FieldBuilder
for constructing a field.
sourceimpl<T> Field<T>where
T: Form,
impl<T> Field<T>where
T: Form,
sourcepub fn name(&self) -> Option<&T::String>
pub fn name(&self) -> Option<&T::String>
Returns the name of the field. None for unnamed fields.
sourcepub fn type_name(&self) -> Option<&T::String>
pub fn type_name(&self) -> Option<&T::String>
Returns a string which is the name of the type of the field as it appears in the source code. The exact contents and format of the type name are not specified, but in practice will be the name of any valid type for a field. This is intended for informational and diagnostic purposes only.
Trait Implementations
sourceimpl<T: Clone + Form> Clone for Field<T>where
T::String: Clone,
T::Type: Clone,
T::String: Clone,
T::String: Clone,
impl<T: Clone + Form> Clone for Field<T>where
T::String: Clone,
T::Type: Clone,
T::String: Clone,
T::String: Clone,
sourceimpl<T: Debug + Form> Debug for Field<T>where
T::String: Debug,
T::Type: Debug,
T::String: Debug,
T::String: Debug,
impl<T: Debug + Form> Debug for Field<T>where
T::String: Debug,
T::Type: Debug,
T::String: Debug,
T::String: Debug,
sourceimpl<T: Form> Decode for Field<T>where
Option<T::String>: Decode,
Option<T::String>: Decode,
T::Type: Decode,
T::Type: Decode,
Option<T::String>: Decode,
Option<T::String>: Decode,
Vec<T::String>: Decode,
Vec<T::String>: Decode,
impl<T: Form> Decode for Field<T>where
Option<T::String>: Decode,
Option<T::String>: Decode,
T::Type: Decode,
T::Type: Decode,
Option<T::String>: Decode,
Option<T::String>: Decode,
Vec<T::String>: Decode,
Vec<T::String>: Decode,
sourcefn decode<__CodecInputEdqy: Input>(
__codec_input_edqy: &mut __CodecInputEdqy
) -> Result<Self, Error>
fn decode<__CodecInputEdqy: Input>(
__codec_input_edqy: &mut __CodecInputEdqy
) -> Result<Self, Error>
Attempt to deserialise the value from input.
sourcefn skip<I>(input: &mut I) -> Result<(), Error>where
I: Input,
fn skip<I>(input: &mut I) -> Result<(), Error>where
I: Input,
Attempt to skip the encoded value from input. Read more
sourcefn encoded_fixed_size() -> Option<usize>
fn encoded_fixed_size() -> Option<usize>
Returns the fixed encoded size of the type. Read more
sourceimpl<T: Form> Encode for Field<T>where
Option<T::String>: Encode,
Option<T::String>: Encode,
T::Type: Encode,
T::Type: Encode,
Option<T::String>: Encode,
Option<T::String>: Encode,
Vec<T::String>: Encode,
Vec<T::String>: Encode,
impl<T: Form> Encode for Field<T>where
Option<T::String>: Encode,
Option<T::String>: Encode,
T::Type: Encode,
T::Type: Encode,
Option<T::String>: Encode,
Option<T::String>: Encode,
Vec<T::String>: Encode,
Vec<T::String>: Encode,
sourcefn encode_to<__CodecOutputEdqy: Output + ?Sized>(
&self,
__codec_dest_edqy: &mut __CodecOutputEdqy
)
fn encode_to<__CodecOutputEdqy: Output + ?Sized>(
&self,
__codec_dest_edqy: &mut __CodecOutputEdqy
)
Convert self to a slice and append it to the destination.
sourcefn size_hint(&self) -> usize
fn size_hint(&self) -> usize
If possible give a hint of expected size of the encoding. Read more
sourcefn encode(&self) -> Vec<u8, Global>ⓘNotable traits for Vec<u8, A>impl<A> Write for Vec<u8, A>where
A: Allocator,
fn encode(&self) -> Vec<u8, Global>ⓘNotable traits for Vec<u8, A>impl<A> Write for Vec<u8, A>where
A: Allocator,
A: Allocator,
Convert self to an owned vector.
sourcefn using_encoded<R, F>(&self, f: F) -> Rwhere
F: FnOnce(&[u8]) -> R,
fn using_encoded<R, F>(&self, f: F) -> Rwhere
F: FnOnce(&[u8]) -> R,
Convert self to a slice and then invoke the given closure with it.
sourcefn encoded_size(&self) -> usize
fn encoded_size(&self) -> usize
Calculates the encoded size. Read more
sourceimpl IntoPortable for Field
impl IntoPortable for Field
type Output = Field<PortableForm>
type Output = Field<PortableForm>
The portable version of Self
.
sourcefn into_portable(self, registry: &mut Registry) -> Self::Output
fn into_portable(self, registry: &mut Registry) -> Self::Output
Convert self
to the portable form by using the registry for caching.
sourceimpl<T: Ord + Form> Ord for Field<T>where
T::String: Ord,
T::Type: Ord,
T::String: Ord,
T::String: Ord,
impl<T: Ord + Form> Ord for Field<T>where
T::String: Ord,
T::Type: Ord,
T::String: Ord,
T::String: Ord,
1.21.0 · sourcefn max(self, other: Self) -> Self
fn max(self, other: Self) -> Self
Compares and returns the maximum of two values. Read more
1.21.0 · sourcefn min(self, other: Self) -> Self
fn min(self, other: Self) -> Self
Compares and returns the minimum of two values. Read more
1.50.0 · sourcefn clamp(self, min: Self, max: Self) -> Selfwhere
Self: PartialOrd<Self>,
fn clamp(self, min: Self, max: Self) -> Selfwhere
Self: PartialOrd<Self>,
Restrict a value to a certain interval. Read more
sourceimpl<T: PartialEq + Form> PartialEq<Field<T>> for Field<T>where
T::String: PartialEq,
T::Type: PartialEq,
T::String: PartialEq,
T::String: PartialEq,
impl<T: PartialEq + Form> PartialEq<Field<T>> for Field<T>where
T::String: PartialEq,
T::Type: PartialEq,
T::String: PartialEq,
T::String: PartialEq,
sourceimpl<T: PartialOrd + Form> PartialOrd<Field<T>> for Field<T>where
T::String: PartialOrd,
T::Type: PartialOrd,
T::String: PartialOrd,
T::String: PartialOrd,
impl<T: PartialOrd + Form> PartialOrd<Field<T>> for Field<T>where
T::String: PartialOrd,
T::Type: PartialOrd,
T::String: PartialOrd,
T::String: PartialOrd,
sourcefn partial_cmp(&self, other: &Field<T>) -> Option<Ordering>
fn partial_cmp(&self, other: &Field<T>) -> Option<Ordering>
This method returns an ordering between self
and other
values if one exists. Read more
1.0.0 · sourcefn lt(&self, other: &Rhs) -> bool
fn lt(&self, other: &Rhs) -> bool
This method tests less than (for self
and other
) and is used by the <
operator. Read more
1.0.0 · sourcefn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
This method tests less than or equal to (for self
and other
) and is used by the <=
operator. Read more
impl<T: Form> EncodeLike<Field<T>> for Field<T>where
Option<T::String>: Encode,
Option<T::String>: Encode,
T::Type: Encode,
T::Type: Encode,
Option<T::String>: Encode,
Option<T::String>: Encode,
Vec<T::String>: Encode,
Vec<T::String>: Encode,
impl<T: Eq + Form> Eq for Field<T>where
T::String: Eq,
T::Type: Eq,
T::String: Eq,
T::String: Eq,
impl<T: Form> StructuralEq for Field<T>
impl<T: Form> StructuralPartialEq for Field<T>
Auto Trait Implementations
impl<T> RefUnwindSafe for Field<T>where
<T as Form>::String: RefUnwindSafe,
<T as Form>::Type: RefUnwindSafe,
impl<T> Send for Field<T>where
<T as Form>::String: Send,
<T as Form>::Type: Send,
impl<T> Sync for Field<T>where
<T as Form>::String: Sync,
<T as Form>::Type: Sync,
impl<T> Unpin for Field<T>where
<T as Form>::String: Unpin,
<T as Form>::Type: Unpin,
impl<T> UnwindSafe for Field<T>where
<T as Form>::String: UnwindSafe,
<T as Form>::Type: UnwindSafe,
Blanket Implementations
sourceimpl<T> BorrowMut<T> for Twhere
T: ?Sized,
impl<T> BorrowMut<T> for Twhere
T: ?Sized,
const: unstable · sourcefn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
Mutably borrows from an owned value. Read more