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Crate oak_bash

Crate oak_bash 

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ยง๐Ÿ› ๏ธ Bash Parser Developer Guide

This guide is designed to help you quickly get started with developing and integrating oak-bash.

ยง๐Ÿšฆ Quick Start

Add the dependency to your Cargo.toml:

[dependencies]
oak-bash = { path = "..." }

ยงBasic Parsing Example

The following is a standard workflow for parsing a Bash script with functions, loops, and redirections:

use oak_bash::{BashParser, SourceText, BashLanguage};

fn main() {
    // 1. Prepare source code
    let code = r#"
        #!/bin/bash

        function greet() {
            local name=$1
            echo "Hello, ${name}!" >&2
        }

        for i in {1..5}; do
            greet "User $i"
        done
    "#;
    let source = SourceText::new(code);

    // 2. Initialize parser
    let config = BashLanguage::new();
    let parser = BashParser::new(&config);

    // 3. Execute parsing
    let result = parser.parse(&source);

    // 4. Handle results
    if result.is_success() {
        println!("Parsing successful! AST node count: {}", result.node_count());
    } else {
        eprintln!("Errors found during parsing.");
        for diag in result.diagnostics() {
            println!("[{}:{}] {}", diag.line, diag.column, diag.message);
        }
    }
}

ยง๐Ÿ” Core API Usage

ยง1. Syntax Tree Traversal

After a successful parse, you can use the built-in visitor pattern or manually traverse the Green/Red Tree to extract Bash specific constructs like function definitions, command pipelines, variable expansions, and redirections.

ยง2. Incremental Parsing

Bash scripts can sometimes be long and complex. oak-bash supports sub-millisecond incremental updates:

// Re-parse only the modified section
let new_result = parser.reparse(&new_source, &old_result);

ยง3. Expansion Awareness

The parser identifies different types of shell expansions (parameter, command, arithmetic), providing a solid foundation for building advanced static analysis tools.

ยง๐Ÿ—๏ธ Architecture Overview

  • Lexer: Tokenizes Bash source text, handling complex rules for word splitting, quoting (single, double, ANSI-C), and comment identification.
  • Parser: A high-performance syntax analyzer that handles Bashโ€™s flexible grammar, including control structures and redirections.
  • AST: A strongly-typed, lossless syntax tree that preserves all trivia (comments/whitespace) for refactoring and formatting tools.

ยง๐Ÿ”— Advanced Resources

  • Full Examples: Check the examples/ folder in the project root.
  • API Documentation: Run cargo doc --open for detailed type definitions.
  • Test Cases: See tests/readme.md for handling of various Bash syntax edge cases. Bash support for the Oak language framework.

Re-exportsยง

pub use crate::ast::BashRoot;
pub use crate::builder::BashBuilder;
pub use crate::language::BashLanguage;
pub use crate::lexer::token_type::BashTokenType;
pub use crate::parser::BashParser;
pub use crate::parser::element_type::BashElementType;

Modulesยง

ast
AST module.
builder
Builder module.
language
Syntax kind module. Language configuration module.
lexer
Lexer module.
lsp
Bash Lsp
parser
Parser module.