plcopen 0.3.0

# plcopen

Parser for PLCopen TC6 XML files - the IEC 61131-3 standard exchange format for PLC programs.

## Features

- Type-safe parsing using quick-xml and serde
- Generated types from the official PLCopen TC6 XML schema (v2.01)
- ST (Structured Text) extraction and parsing via `iec61131`

## Installation

```bash
cargo add plcopen
```

Or add to your `Cargo.toml`:

```toml
[dependencies]
plcopen = "0.3"
```

## Usage

```rust
use plcopen::Project;

// Parse PLCopen XML file
let xml = std::fs::read_to_string("project.xml")?;
let project: Project = plcopen::from_str(&xml)?;
println!("Project: {:?}", project);
```

## ST Code Extraction

```rust
use plcopen::st::{extract_all_st_from_xml, parse_st};

let xml = std::fs::read_to_string("project.xml")?;

// Extract all ST code blocks from POUs
for (pou_name, st_code) in extract_all_st_from_xml(&xml) {
    // Parse ST code into AST
    let statements = parse_st(&st_code)?;
    println!("{}: {} statements", pou_name, statements.len());
}
```

## PLCopen TC6 XML Format

PLCopen TC6 is an XML-based exchange format defined by the PLCopen organization 
for transferring PLC programs between different development environments.

This parser handles:
- **Program Organization Units (POUs)**: Programs, Functions, Function Blocks
- **Data Types**: Elementary types (BOOL, INT, REAL, etc.) and user-defined types
- **Variables**: Input, Output, InOut, Local, Global, External
- **ST Code Extraction**: Extracts and parses Structured Text (ST) code using `iec61131`

**Note**: The XML format supports all 5 IEC 61131-3 languages (ST, IL, LD, FBD, SFC), 
but this parser currently only extracts and parses ST (Structured Text) code

## License

MIT