synta 0.2.0

ASN.1 parser, decoder, and encoder library with DER/BER support and C FFI
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# Naming Conventions

synta-codegen converts ASN.1 identifiers to idiomatic Rust names following
rules in `naming.rs`.  Three categories are covered: type names, field names,
and named-value constants.

## Type names — PascalCase

Each hyphen-delimited segment is converted: first character uppercased,
remaining characters lowercased.  An all-caps heuristic applies per segment,
not per character.

| ASN.1 name | Rust name |
|---|---|
| `Certificate` | `Certificate` |
| `KDC-REQ` | `KdcReq` |
| `TBSCertificate` | `TBSCertificate` |
| `my-Type` | `MyType` |
| `PA-DATA` | `PaData` |
| `ETYPE-INFO2` | `EtypeInfo2` |
| `KRB-ERROR` | `KrbError` |

## Field names — snake_case

Hyphens are replaced with underscores.  Rust keywords receive an `r#` prefix.

| ASN.1 field name | Rust field name |
|---|---|
| `serialNumber` | `serial_number` |
| `issuer-unique-id` | `issuer_unique_id` |
| `type` | `r#type` |
| `mod` | `r#mod` |
| `version` | `version` |

Note: `r#from` is needed only in expression position (e.g., struct constructor
calls).  Field definitions use `from` directly without `r#`.

## Named value constants — SCREAMING_SNAKE_CASE

Named values in INTEGER or ENUMERATED types are placed as associated constants
on the generated type.

ASN.1:

```asn1
Protocol ::= INTEGER { tcp(6), udp(17) }
```

Generated Rust:

```rust
pub struct Protocol(pub synta::Integer);

impl Protocol {
    pub const TCP: i64 = 6;
    pub const UDP: i64 = 17;
}
```

## Module names in use statements

ASN.1 module names are converted to snake_case when used in Rust `use` paths.
Each hyphen-separated segment is lowercased independently; camelCase boundaries
are split before each uppercase letter that follows a lowercase letter.

| ASN.1 module name | Rust path segment |
|---|---|
| `BaseTypes` | `base_types` |
| `UserModule` | `user_module` |
| `CamelCaseModule` | `camel_case_module` |
| `kebab-case-module` | `kebab_case_module` |
| `SCREAMING-CASE` | `screaming_case` |
| `PKIX1Explicit88` | `pkix1explicit88` |

The module name from the ASN.1 `DEFINITIONS` header is used, not the file name.

## CLI example

```sh
# Generates: struct KdcReq { ... }
synta-codegen kerberos.asn1 -o src/kerberos.rs
```