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Crate midds_types_codegen

Crate midds_types_codegen 

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§MIDDS Types Code Generation

This crate provides procedural macros for generating bounded string and collection types that are compatible with Substrate runtime and WebAssembly bindings.

The main purpose is to solve the limitation where wasm_bindgen doesn’t support generic parameters, preventing the use of BoundedVec<T, Bound> directly in JavaScript-exposed APIs.

§Features

  • #[midds_string(bound)]: Generates bounded string types with UTF-8 validation
  • #[midds_collection(type, bound)]: Generates bounded collection types
  • Substrate compatibility: Implements all required traits for runtime usage
  • JavaScript bindings: Provides wasm_bindgen integration when the js feature is enabled
  • Type safety: Compile-time bounds checking and UTF-8 validation
  • Serde support: Automatic Serialize/Deserialize implementation when the js feature is enabled

§Usage

use midds_types_codegen::{midds_string, midds_collection};

// Generate a bounded string type with 256-byte limit
#[midds_string(256)]
pub struct TrackTitle;

// Generate a bounded collection type for 64 u64 values
#[midds_collection(u64, 64)]
pub struct ProducerIds;

§Generated API

Each macro generates a complete API including:

  • Standard trait implementations (Clone, PartialEq, Encode, Decode, etc.)
  • String/collection manipulation methods
  • Error handling with type-specific error enums
  • JavaScript bindings (when js feature is enabled)

§Architecture

The generated types wrap sp_runtime::BoundedVec to provide:

  • Compile-time capacity limits
  • Runtime bounds checking
  • Memory-efficient storage
  • Substrate runtime compatibility

Attribute Macros§

midds_collection
Procedural macro that generates a bounded collection type with compile-time capacity limits.
midds_string
Procedural macro that generates a bounded string type with compile-time capacity limits.