Struct ReadsContract 

#[non_exhaustive]
pub struct ReadsContract {
    pub required: &'static [&'static str],
    pub exactly_one_of: &'static [&'static [&'static str]],
    pub with_field_requires: &'static [(&'static str, &'static str)],
}

What an action requires of its step’s reads: map.

See ActionType::reads_contract.

Fields (Non-exhaustive)

Non-exhaustive structs could have additional fields added in future. Therefore, non-exhaustive structs cannot be constructed in external crates using the traditional Struct { .. } syntax; cannot be matched against without a wildcard ..; and struct update syntax will not work.

required: &'static [&'static str]

Inputs every step of this action must name.

exactly_one_of: &'static [&'static [&'static str]]

Groups from which exactly one input must be named. Each group holds the alternatives in the order they should be listed to the author.

with_field_requires: &'static [(&'static str, &'static str)]

with: fields that mean nothing unless the step also names a given input, as (field, input) pairs.

Where an action offers two paths over one operation, a parameter can belong to only one of them. On the other path it would be parsed and never read, so the step would run without whatever the parameter asked for. This says which parameter needs which input.

Implementations

impl ReadsContract

pub const NONE: Self

The contract of an action that constrains its inputs in neither way.

pub const fn required(fields: &'static [&'static str]) -> Self

The contract of an action that requires these inputs and offers no alternatives between them.

pub fn is_empty(&self) -> bool

Whether this contract constrains the reads: map at all.

with_field_requires is a rule over with:, so it is not counted here.

Trait Implementations

impl Clone for ReadsContract

fn clone(&self) -> ReadsContract

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for ReadsContract

impl Debug for ReadsContract

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

Formats the value using the given formatter.

impl Eq for ReadsContract

impl PartialEq for ReadsContract

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for ReadsContract