@taml/parser

Robust parser that converts TAML markup strings into typed AST nodes with comprehensive error handling and validation.

TAML Ecosystem

TAML (Terminal ANSI Markup Language) is a lightweight markup language for styling terminal output with ANSI escape codes. For the complete specification, visit the TAML Specification Repository.

Package Dependencies

graph TD
    B["@taml/parser"] --> A["@taml/ast"]
    C["@taml/react"] --> A
    C --> B
    D["@taml/docusaurus"] --> C
    F["@taml/cli"] --> E["@taml/encoder"]
    E -.-> A
    E -.-> B
    style B fill:#e1f5fe,stroke:#01579b,stroke-width:2px

Related Packages

Core Infrastructure

@taml/ast - Foundation package providing AST node types, visitor patterns, and tree traversal utilities for TAML documents.
@taml/parser - Robust parser that converts TAML markup strings into typed AST nodes with comprehensive error handling and validation.

Input/Output Tools

@taml/encoder - Converts raw ANSI escape sequences into clean TAML markup for further processing and manipulation.
@taml/cli - Command-line tool for converting ANSI escape sequences to TAML format in batch operations.

Integration Packages

@taml/react - React component that renders TAML markup as styled JSX elements with full TypeScript support and performance optimization.
@taml/docusaurus - Docusaurus theme that automatically detects and renders TAML code blocks in documentation sites.

Installation

npm

npm install @taml/parser

yarn

yarn add @taml/parser

pnpm

pnpm add @taml/parser

bun

bun add @taml/parser

TypeScript Setup

This package includes TypeScript declarations out of the box. No additional setup is required for TypeScript projects. The package automatically includes @taml/ast as a dependency for AST node types.

// ESM
import { parseTaml, parseTamlSafe, validateTaml } from "@taml/parser";

// CommonJS
const { parseTaml, parseTamlSafe, validateTaml } = require("@taml/parser");

Quick Start

Here's a 5-minute introduction to parsing TAML markup into structured AST trees:

import { parseTaml, parseTamlSafe, validateTaml } from "@taml/parser";
import { getAllText, getElementsWithTag, visit } from "@taml/ast";

// Basic parsing
const ast = parseTaml("<red>Hello <bold>World</bold>!</red>");
console.log(getAllText(ast)); // "Hello World!"

// Safe parsing with error handling
const result = parseTamlSafe("<red>Hello <bold>World</bold></red>");
if (result.success) {
  console.log("Parsed successfully:", getAllText(result.ast));

  // Find specific elements
  const redElements = getElementsWithTag(result.ast, "red");
  const boldElements = getElementsWithTag(result.ast, "bold");

  console.log(`Found ${redElements.length} red elements`);
  console.log(`Found ${boldElements.length} bold elements`);
} else {
  console.error("Parse error:", result.error.message);
}

// Validation without full parsing
const validation = validateTaml("<green>Success!</green>");
if (validation.valid) {
  console.log("Valid TAML syntax");
} else {
  validation.errors.forEach((error) => console.error(error.message));
}

// Advanced usage with visitor pattern
visit(ast, {
  visitElement: (node) => {
    console.log(
      `Found ${node.tagName} element with ${node.children.length} children`,
    );
  },
  visitText: (node) => {
    console.log(`Text content: "${node.content}"`);
  },
});

Core Concepts

Parser Architecture

The TAML parser follows a multi-stage architecture for robust and efficient parsing:

1. Tokenization

Converts raw TAML markup into a stream of typed tokens (open tags, close tags, text content).

2. Validation

Validates token sequences against TAML specification rules and nesting requirements.

3. AST Construction

Builds a typed Abstract Syntax Tree from validated tokens with proper parent-child relationships.

4. Error Handling

Provides detailed error messages with line/column information for debugging.

Supported TAML Features

The parser supports all 37 valid TAML tags from the specification:

Standard Colors

Foreground: black, red, green, yellow, blue, magenta, cyan, white
Background: bgBlack, bgRed, bgGreen, bgYellow, bgBlue, bgMagenta, bgCyan, bgWhite

Bright Colors

Foreground: brightBlack, brightRed, brightGreen, brightYellow, brightBlue, brightMagenta, brightCyan, brightWhite
Background: bgBrightBlack, bgBrightRed, bgBrightGreen, bgBrightYellow, bgBrightBlue, bgBrightMagenta, bgBrightCyan, bgBrightWhite

Text Styles

Formatting: bold, dim, italic, underline, strikethrough

Error Handling Approach

The parser uses a strict validation approach with comprehensive error reporting:

Position Tracking: All errors include precise line and column information
Context Preservation: Error messages show surrounding source code
Error Recovery: Safe parsing functions allow graceful error handling
Detailed Messages: Specific error types with actionable feedback

Usage Examples

Basic Parsing

Simple Color Tags

import { parseTaml } from "@taml/parser";
import { getAllText } from "@taml/ast";

// Parse basic color formatting
const errorAst = parseTaml("<red>Error:</red> File not found");
console.log(getAllText(errorAst)); // "Error: File not found"

// Parse success message
const successAst = parseTaml("<green>✓</green> Operation completed");
console.log(getAllText(successAst)); // "✓ Operation completed"

// Parse warning with multiple styles
const warningAst = parseTaml(
  "<yellow><bold>Warning:</bold></yellow> Deprecated API",
);
console.log(getAllText(warningAst)); // "Warning: Deprecated API"

Text Formatting

// Bold and italic text
const styledAst = parseTaml(
  "<bold>Important:</bold> <italic>Please read carefully</italic>",
);

// Underlined links
const linkAst = parseTaml(
  "Visit <underline>https://example.com</underline> for details",
);

// Strikethrough for deletions
const deletedAst = parseTaml(
  "Old: <strikethrough>deprecated method</strikethrough>",
);

Complex Nesting

Nested Formatting

// Complex nested structure
const complexAst = parseTaml(`
  <bold>
    <red>ERROR:</red>
    <underline>config.json</underline>:<yellow>line 42</yellow>
    <dim>(validation failed)</dim>
  </bold>
`);

// Log entry with multiple levels
const logAst = parseTaml(`
  <dim>2024-01-15 10:30:15</dim>
  <red>[ERROR]</red>
  <bold>Database connection failed</bold>
  <dim>
    Connection string: <underline>postgresql://localhost:5432/app</underline>
    Retry attempt: <yellow>3/5</yellow>
  </dim>
`);

Terminal Output Simulation

// Git status output
const gitStatusAst = parseTaml(`
  On branch <green>main</green>
  Your branch is up to date with 'origin/main'.
  
  Changes not staged for commit:
    <red>modified:   src/app.ts</red>
    <red>modified:   README.md</red>
  
  Untracked files:
    <red>new-feature.ts</red>
`);

// Build output with progress
const buildAst = parseTaml(`
  <bold><blue>Building application...</blue></bold>
  
  <green>✓</green> TypeScript compilation <dim>(2.3s)</dim>
  <green>✓</green> Asset bundling <dim>(1.8s)</dim>
  <yellow>⚠</yellow> Bundle size: <bold>2.1MB</bold> <dim>(consider optimization)</dim>
  <green>✓</green> Build completed <dim>(4.1s total)</dim>
`);

Error Recovery Patterns

Safe Parsing with Error Handling

import { parseTamlSafe } from "@taml/parser";

const sources = [
  "<red>Valid content</red>",
  "<red>Unclosed content",
  "<red>Content</blue>",
  "<invalidTag>Invalid tag</invalidTag>",
  "<red>Nested <bold>content</red></bold>", // Mismatched nesting
];

sources.forEach((source, index) => {
  const result = parseTamlSafe(source);
  if (result.success) {
    console.log(`Source ${index}: Parsed successfully`);
    console.log(`Content: "${getAllText(result.ast)}"`);
  } else {
    console.log(`Source ${index}: ${result.error.message}`);

    // Handle specific error types
    if (result.error instanceof UnclosedTagError) {
      console.log(`  → Unclosed tag: ${result.error.tagName}`);
    } else if (result.error instanceof MismatchedTagError) {
      console.log(
        `  → Expected: ${result.error.expected}, Got: ${result.error.actual}`,
      );
    } else if (result.error instanceof InvalidTagError) {
      console.log(`  → Invalid tag: ${result.error.tagName}`);
    }
  }
});

Validation Before Parsing

import { validateTaml, parseTaml } from "@taml/parser";

function safeParseWithValidation(source: string) {
  // First validate the syntax
  const validation = validateTaml(source);

  if (!validation.valid) {
    console.error("Validation failed:");
    validation.errors.forEach((error, index) => {
      console.error(`  ${index + 1}. ${error.message}`);
    });
    return null;
  }

  // If valid, parse safely
  return parseTaml(source);
}

// Usage
const ast = safeParseWithValidation("<red>Hello <bold>World</bold></red>");
if (ast) {
  console.log("Successfully parsed:", getAllText(ast));
}

Real-World Use Cases

Log File Processing

import { parseTaml, parseTamlSafe } from "@taml/parser";
import { visit, getElementsWithTag } from "@taml/ast";

// Process application logs with TAML formatting
function processLogEntry(tamlLog: string) {
  const result = parseTamlSafe(tamlLog);

  if (!result.success) {
    console.warn("Failed to parse log entry:", result.error.message);
    return null;
  }

  const ast = result.ast;

  // Extract log level
  const errorElements = getElementsWithTag(ast, "red");
  const warningElements = getElementsWithTag(ast, "yellow");
  const infoElements = getElementsWithTag(ast, "green");

  // Determine log level
  let level = "DEBUG";
  if (errorElements.length > 0) level = "ERROR";
  else if (warningElements.length > 0) level = "WARN";
  else if (infoElements.length > 0) level = "INFO";

  // Extract plain text content
  const message = getAllText(ast);

  return {
    level,
    message,
    hasFormatting:
      errorElements.length + warningElements.length + infoElements.length > 0,
    ast,
  };
}

// Example usage
const logEntries = [
  "<dim>2024-01-15 10:30:15</dim> <green>[INFO]</green> Server started",
  "<dim>2024-01-15 10:30:16</dim> <yellow>[WARN]</yellow> High memory usage",
  "<dim>2024-01-15 10:30:17</dim> <red>[ERROR]</red> Database connection failed",
];

logEntries.forEach((entry) => {
  const processed = processLogEntry(entry);
  if (processed) {
    console.log(`[${processed.level}] ${processed.message}`);
  }
});

Terminal Command Documentation

// Parse command help output with TAML formatting
const commandHelp = parseTaml(`
  <bold>Usage:</bold> myapp <green>[command]</green> <yellow>[options]</yellow>
  
  <bold>Commands:</bold>
    <green>start</green>     Start the application
    <green>stop</green>      Stop the application
    <green>restart</green>   Restart the application
    <green>status</green>    Show application status
  
  <bold>Options:</bold>
    <yellow>--port</yellow>     <dim>Port number (default: 3000)</dim>
    <yellow>--env</yellow>      <dim>Environment (dev|prod)</dim>
    <yellow>--verbose</yellow>  <dim>Enable verbose logging</dim>
    <yellow>--help</yellow>     <dim>Show this help message</dim>
  
  <bold>Examples:</bold>
    <dim>myapp start --port 8080</dim>
    <dim>myapp status --verbose</dim>
`);

// Extract structured information
const commands: string[] = [];
const options: string[] = [];

visit(commandHelp, {
  visitElement: (node) => {
    if (node.tagName === "green") {
      const text = getAllText(node).trim();
      if (text && !commands.includes(text)) {
        commands.push(text);
      }
    } else if (node.tagName === "yellow") {
      const text = getAllText(node).trim();
      if (text.startsWith("--") && !options.includes(text)) {
        options.push(text);
      }
    }
  },
});

console.log("Available commands:", commands);
console.log("Available options:", options);

Integration with TAML Ecosystem

With AST Utilities

import { parseTaml } from "@taml/parser";
import {
  visit,
  transform,
  getAllText,
  getElementsWithTag,
  findAll,
  createCollectorVisitor,
} from "@taml/ast";

const ast = parseTaml("<red>Error: <bold>File not found</bold></red>");

// Extract all text content
const plainText = getAllText(ast);
console.log(plainText); // "Error: File not found"

// Find specific elements
const redElements = getElementsWithTag(ast, "red");
const boldElements = getElementsWithTag(ast, "bold");

// Use visitor pattern for analysis
visit(ast, {
  visitElement: (node) => {
    console.log(`Found ${node.tagName} element`);
  },
  visitText: (node) => {
    console.log(`Text: "${node.content}"`);
  },
});

// Transform to different format
const html = transform(ast, {
  visitDocument: (node) =>
    node.children.map((child) => transform(child, this)).join(""),
  visitElement: (node) => {
    const content = node.children
      .map((child) => transform(child, this))
      .join("");
    return `<span class="taml-${node.tagName}">${content}</span>`;
  },
  visitText: (node) => node.content,
});

console.log(html); // '<span class="taml-red">Error: <span class="taml-bold">File not found</span></span>'

With Encoder

import { encode } from "@taml/encoder";
import { parseTaml } from "@taml/parser";
import { getAllText, visit } from "@taml/ast";

// Complete ANSI → TAML → AST pipeline
const ansiText = "\x1b[31mError:\x1b[0m \x1b[1mFile not found\x1b[0m";

// 1. Convert ANSI to TAML
const tamlMarkup = encode(ansiText);
console.log("TAML:", tamlMarkup); // "<red>Error:</red> <bold>File not found</bold>"

// 2. Parse TAML to AST
const ast = parseTaml(tamlMarkup);

// 3. Analyze the parsed content
const plainText = getAllText(ast);
console.log("Plain text:", plainText); // "Error: File not found"

// 4. Count formatting elements
let errorCount = 0;
let emphasisCount = 0;

visit(ast, {
  visitElement: (node) => {
    if (node.tagName === "red") errorCount++;
    if (node.tagName === "bold") emphasisCount++;
  },
});

console.log(
  `Found ${errorCount} error indicators, ${emphasisCount} emphasis elements`,
);

With React Components

import { parseTaml } from '@taml/parser';
import { TamlRenderer } from '@taml/react';

function LogViewer({ tamlContent }: { tamlContent: string }) {
  const ast = parseTaml(tamlContent);

  return (
    <div className="log-viewer">
      <TamlRenderer ast={ast} />
    </div>
  );
}

// Usage
const logEntry = '<dim>2024-01-15 10:30:15</dim> <red>[ERROR]</red> <bold>Connection failed</bold>';
<LogViewer tamlContent={logEntry} />

With CLI Tools

# Convert ANSI to TAML, then parse and analyze
echo -e "\033[31mError:\033[0m \033[1mFailed\033[0m" | taml-cli | node -e "
  const { parseTaml } = require('@taml/parser');
  const { getAllText, getElementsWithTag } = require('@taml/ast');

  let input = '';
  process.stdin.on('data', chunk => input += chunk);
  process.stdin.on('end', () => {
    const ast = parseTaml(input.trim());
    const plainText = getAllText(ast);
    const errorElements = getElementsWithTag(ast, 'red');

    console.log('Plain text:', plainText);
    console.log('Error count:', errorElements.length);
  });
"

Complete Processing Pipeline

import { encode } from "@taml/encoder";
import { parseTaml, parseTamlSafe } from "@taml/parser";
import { visit, transform, getAllText, getElementsWithTag } from "@taml/ast";

// Complete ANSI → TAML → AST → Analysis → Output pipeline
class TamlProcessor {
  processAnsiOutput(ansiText: string) {
    // 1. Convert ANSI to TAML
    const tamlMarkup = encode(ansiText);

    // 2. Parse TAML to AST with error handling
    const parseResult = parseTamlSafe(tamlMarkup);

    if (!parseResult.success) {
      return {
        success: false,
        error: parseResult.error.message,
        originalText: ansiText,
      };
    }

    const ast = parseResult.ast;

    // 3. Extract information
    const plainText = getAllText(ast);
    const errorElements = getElementsWithTag(ast, "red");
    const warningElements = getElementsWithTag(ast, "yellow");
    const successElements = getElementsWithTag(ast, "green");

    // 4. Transform to different formats
    const html = transform(ast, {
      visitDocument: (node) =>
        `<div class="taml-output">${node.children.map((child) => transform(child, this)).join("")}</div>`,
      visitElement: (node) => {
        const content = node.children
          .map((child) => transform(child, this))
          .join("");
        return `<span class="taml-${node.tagName}">${content}</span>`;
      },
      visitText: (node) => this.escapeHtml(node.content),
    });

    // 5. Analyze content
    const analysis = {
      hasErrors: errorElements.length > 0,
      hasWarnings: warningElements.length > 0,
      hasSuccess: successElements.length > 0,
      elementCounts: {
        errors: errorElements.length,
        warnings: warningElements.length,
        success: successElements.length,
      },
    };

    return {
      success: true,
      originalAnsi: ansiText,
      tamlMarkup,
      plainText,
      html,
      analysis,
      ast,
    };
  }

  private escapeHtml(text: string): string {
    return text
      .replace(/&/g, "&amp;")
      .replace(/</g, "&lt;")
      .replace(/>/g, "&gt;")
      .replace(/"/g, "&quot;")
      .replace(/'/g, "&#39;");
  }
}

// Usage
const processor = new TamlProcessor();
const ansiOutput =
  "\x1b[31mERROR:\x1b[0m \x1b[1mDatabase connection failed\x1b[0m";
const result = processor.processAnsiOutput(ansiOutput);

if (result.success) {
  console.log("Plain text:", result.plainText);
  console.log("HTML:", result.html);
  console.log("Analysis:", result.analysis);
} else {
  console.error("Processing failed:", result.error);
}

API Reference

Main Functions

`parseTaml(source, options?)`

Parses TAML source text and returns a DocumentNode AST.

function parseTaml(source: string, options?: ParseOptions): DocumentNode;

Parameters:

source - TAML source text to parse
options - Optional parsing configuration

Returns: DocumentNode - Root AST node

Throws: Various error types for invalid syntax (see Error Handling)

Example:

const ast = parseTaml("<green>[SUCCESS]</green> Operation completed");
console.log(ast.children.length); // 2 (element + text)

`parseTamlSafe(source, options?)`

Safe parsing that returns a result object instead of throwing errors.

function parseTamlSafe(
  source: string,
  options?: ParseOptions,
): {
  success: boolean;
  ast?: DocumentNode;
  error?: Error;
};

Example:

const result = parseTamlSafe("<red>Unclosed tag");
if (!result.success) {
  console.error("Parse failed:", result.error?.message);
} else {
  console.log("Parsed successfully:", getAllText(result.ast));
}

`validateTaml(source)`

Validates TAML syntax without building the full AST.

function validateTaml(source: string): {
  valid: boolean;
  errors: Error[];
};

Example:

const { valid, errors } = validateTaml("<red>Hello</blue>");
if (!valid) {
  errors.forEach((error) => console.error(error.message));
}

Parse Options

`ParseOptions` Interface

interface ParseOptions {
  /** Whether to include position information in nodes (default: true) */
  includePositions?: boolean;
  /** Maximum nesting depth to prevent stack overflow (default: 100) */
  maxDepth?: number;
}

Examples:

// Parse without position information (smaller AST)
const ast = parseTaml("<red>Hello</red>", { includePositions: false });

// Parse with custom depth limit
const ast = parseTaml(deeplyNested, { maxDepth: 50 });

Advanced Usage

`TamlParser` Class

For advanced use cases, you can use the parser class directly:

import { TamlParser } from "@taml/parser";

const parser = new TamlParser("<red>Hello World</red>");
const ast = parser.parse();

// Parse with options
const astWithOptions = parser.parseWithOptions({
  includePositions: true,
  maxDepth: 100,
});

Tokenization

Access the tokenization layer for advanced processing:

import { tokenize, TamlTokenizer } from "@taml/parser";

// Quick tokenization
const tokens = tokenize("<red>Hello</red>");
console.log(tokens.length); // 4 tokens: open-tag, text, close-tag, eof

// Advanced tokenization with class
const tokenizer = new TamlTokenizer("<red>Hello</red>");
const tokens = tokenizer.tokenize();

// Inspect tokens
tokens.forEach((token) => {
  console.log(`${token.type}: ${token.value} at ${token.line}:${token.column}`);
});

Validation

Use the validator for detailed syntax checking:

import { TamlValidator, validateTamlTokens } from "@taml/parser";

// Validate with class
const validator = new TamlValidator("<red>Hello</red>");
const tokens = tokenize("<red>Hello</red>");
const result = validator.validateTokens(tokens);

// Direct token validation
const validationResult = validateTamlTokens(tokens, "<red>Hello</red>");
console.log("Valid:", validationResult.valid);
console.log("Errors:", validationResult.errors);

Error Handling

The parser uses a strict validation approach and throws detailed errors for any invalid syntax.

Error Types

`TamlParseError`

Base class for all parsing errors with position information.

class TamlParseError extends Error {
  constructor(
    message: string,
    public readonly position: number,
    public readonly line: number,
    public readonly column: number,
    public readonly source?: string
  )
}

`InvalidTagError`

Thrown when an invalid tag name is encountered.

// Throws InvalidTagError
parseTaml("<invalidTag>content</invalidTag>");

`UnclosedTagError`

Thrown when a tag is not properly closed.

// Throws UnclosedTagError
parseTaml("<red>unclosed content");

`MismatchedTagError`

Thrown when closing tag doesn't match opening tag.

// Throws MismatchedTagError
parseTaml("<red>content</blue>");

`MalformedTagError`

Thrown when a tag is malformed (invalid syntax).

// Throws MalformedTagError
parseTaml("<>empty tag name</>");
parseTaml("<red-invalid>hyphen in name</red-invalid>");

`UnexpectedEndOfInputError`

Thrown when input ends unexpectedly.

`UnexpectedCharacterError`

Thrown when an unexpected character is encountered.

Error Context

All errors include detailed context information:

import {
  parseTaml,
  MismatchedTagError,
  UnclosedTagError,
  InvalidTagError,
} from "@taml/parser";

try {
  parseTaml("line1\n<red>line2\nline3</blue>");
} catch (error) {
  if (error instanceof MismatchedTagError) {
    console.log(`Error at line ${error.line}, column ${error.column}`);
    console.log(`Expected: ${error.expected}, Got: ${error.actual}`);
    console.log(error.getDetailedMessage()); // Shows source context
  } else if (error instanceof UnclosedTagError) {
    console.log(`Unclosed tag: ${error.tagName}`);
    console.log(error.getDetailedMessage());
  } else if (error instanceof InvalidTagError) {
    console.log(`Invalid tag: ${error.tagName}`);
    console.log(error.getDetailedMessage());
  }
}

Common Error Patterns

Invalid Tag Names

// ❌ Invalid - not in TAML specification
parseTaml("<span>content</span>");
parseTaml("<custom>content</custom>");
parseTaml("<red-color>content</red-color>");

// ✅ Valid - TAML specification tags
parseTaml("<red>content</red>");
parseTaml("<bold>content</bold>");
parseTaml("<brightRed>content</brightRed>");

Nesting Issues

// ❌ Invalid - mismatched tags
parseTaml("<red><bold>content</red></bold>");

// ❌ Invalid - unclosed tags
parseTaml("<red><bold>content</bold>");

// ❌ Invalid - extra closing tags
parseTaml("<red>content</red></bold>");

// ✅ Valid - proper nesting
parseTaml("<red><bold>content</bold></red>");

Malformed Syntax

// ❌ Invalid - malformed tags
parseTaml("<red unclosed");
parseTaml("<123invalid>numeric start</123invalid>");
parseTaml("<red-dash>hyphens not allowed</red-dash>");
parseTaml("<>empty tag name</>");

// ✅ Valid - proper syntax
parseTaml("<red>content</red>");
parseTaml("<brightBlue>content</brightBlue>");

Advanced Topics

Performance Considerations

The parser is optimized for speed, memory efficiency, and detailed error reporting:

Optimization Features

Fast Tokenization: Character-by-character streaming processing
Memory Efficient: Minimal object allocation during parsing
Error Context: Detailed error reporting without performance penalty
Depth Control: Configurable nesting limits to prevent stack overflow

Benchmarks

Typical performance on modern hardware:

Simple tags: ~500K operations/second
Complex nesting: ~100K operations/second
Large documents: ~5MB/second parsing speed
Memory usage: ~150 bytes per AST node

Memory Usage

AST overhead: ~100 bytes per node
Position tracking: ~50 bytes per node (when enabled)
Parser state: ~2KB base memory
Token overhead: ~80 bytes per token

Optimization Tips

// Disable position tracking for memory savings
const ast = parseTaml(source, { includePositions: false });

// Use validation for syntax checking without AST building
const { valid } = validateTaml(source);

// Use safe parsing to avoid exception overhead in batch processing
const result = parseTamlSafe(source);

// Set appropriate depth limits for deeply nested content
const ast = parseTaml(source, { maxDepth: 50 });

Error Handling Patterns

Graceful Error Recovery

import { parseTamlSafe, TamlParseError } from "@taml/parser";

function parseWithFallback(source: string, fallbackText?: string) {
  const result = parseTamlSafe(source);

  if (result.success) {
    return result.ast;
  }

  // Log error for debugging
  console.warn("TAML parse failed:", result.error.message);

  // Return fallback AST
  if (fallbackText) {
    return parseTaml(`<red>Parse Error:</red> ${fallbackText}`);
  }

  // Return minimal error AST
  return parseTaml("<red>Invalid TAML syntax</red>");
}

Batch Processing with Error Handling

function parseBatch(sources: string[]): Array<{
  index: number;
  source: string;
  success: boolean;
  ast?: DocumentNode;
  error?: string;
}> {
  return sources.map((source, index) => {
    const result = parseTamlSafe(source);

    if (result.success) {
      return {
        index,
        source,
        success: true,
        ast: result.ast,
      };
    } else {
      return {
        index,
        source,
        success: false,
        error: result.error.message,
      };
    }
  });
}

// Usage
const sources = [
  "<red>Valid</red>",
  "<red>Invalid",
  "<green>Also valid</green>",
];

const results = parseBatch(sources);
const successful = results.filter((r) => r.success);
const failed = results.filter((r) => !r.success);

console.log(`Parsed ${successful.length}/${sources.length} successfully`);
failed.forEach((f) => console.error(`Failed ${f.index}: ${f.error}`));

Custom Error Handling

import {
  TamlParseError,
  InvalidTagError,
  UnclosedTagError,
  MismatchedTagError,
} from "@taml/parser";

class TamlParseErrorHandler {
  handleError(
    error: Error,
    source: string,
  ): {
    type: string;
    message: string;
    suggestion?: string;
    position?: { line: number; column: number };
  } {
    if (!(error instanceof TamlParseError)) {
      return {
        type: "unknown",
        message: error.message,
      };
    }

    const baseInfo = {
      position: { line: error.line, column: error.column },
    };

    if (error instanceof InvalidTagError) {
      return {
        ...baseInfo,
        type: "invalid-tag",
        message: `Invalid tag '${error.tagName}'`,
        suggestion:
          "Use one of the 37 valid TAML tags (red, green, bold, etc.)",
      };
    }

    if (error instanceof UnclosedTagError) {
      return {
        ...baseInfo,
        type: "unclosed-tag",
        message: `Unclosed tag '${error.tagName}'`,
        suggestion: `Add closing tag: </${error.tagName}>`,
      };
    }

    if (error instanceof MismatchedTagError) {
      return {
        ...baseInfo,
        type: "mismatched-tag",
        message: `Expected '</${error.expected}>' but found '</${error.actual}>'`,
        suggestion: `Change closing tag to match opening tag`,
      };
    }

    return {
      ...baseInfo,
      type: "parse-error",
      message: error.message,
    };
  }
}

// Usage
const errorHandler = new TamlParseErrorHandler();

try {
  parseTaml("<red>unclosed");
} catch (error) {
  const handled = errorHandler.handleError(error, "<red>unclosed");
  console.error(`${handled.type}: ${handled.message}`);
  if (handled.suggestion) {
    console.log(`Suggestion: ${handled.suggestion}`);
  }
}

Integration Patterns

Parser Factory Pattern

class TamlParserFactory {
  private defaultOptions: Required<ParseOptions> = {
    includePositions: true,
    maxDepth: 100,
  };

  createParser(options?: Partial<ParseOptions>) {
    const opts = { ...this.defaultOptions, ...options };

    return {
      parse: (source: string) => parseTaml(source, opts),
      parseSafe: (source: string) => parseTamlSafe(source, opts),
      validate: (source: string) => validateTaml(source),
    };
  }

  createLightweightParser() {
    return this.createParser({
      includePositions: false,
      maxDepth: 50,
    });
  }

  createStrictParser() {
    return this.createParser({
      includePositions: true,
      maxDepth: 25,
    });
  }
}

// Usage
const factory = new TamlParserFactory();
const lightParser = factory.createLightweightParser();
const strictParser = factory.createStrictParser();

const ast1 = lightParser.parse("<red>Hello</red>");
const result = strictParser.parseSafe("<red>Hello</red>");

Streaming Parser for Large Documents

class StreamingTamlParser {
  private buffer = "";
  private results: DocumentNode[] = [];

  processChunk(chunk: string): DocumentNode[] {
    this.buffer += chunk;
    const newResults: DocumentNode[] = [];

    // Try to parse complete TAML expressions
    const lines = this.buffer.split("\n");

    // Keep the last incomplete line in buffer
    this.buffer = lines.pop() || "";

    for (const line of lines) {
      if (line.trim()) {
        const result = parseTamlSafe(line.trim());
        if (result.success) {
          newResults.push(result.ast);
          this.results.push(result.ast);
        }
      }
    }

    return newResults;
  }

  finalize(): DocumentNode[] {
    // Process any remaining buffer content
    if (this.buffer.trim()) {
      const result = parseTamlSafe(this.buffer.trim());
      if (result.success) {
        this.results.push(result.ast);
      }
    }

    return this.results;
  }

  getAllResults(): DocumentNode[] {
    return [...this.results];
  }
}

// Usage
const streamParser = new StreamingTamlParser();

// Process chunks as they arrive
const chunk1 = "<red>Error:</red> Connection failed\n<green>Info:</green>";
const chunk2 =
  " Server restarted\n<yellow>Warning:</yellow> High memory usage\n";

const results1 = streamParser.processChunk(chunk1);
const results2 = streamParser.processChunk(chunk2);
const finalResults = streamParser.finalize();

console.log(`Processed ${finalResults.length} TAML expressions`);

Plugin Architecture

interface TamlParserPlugin {
  name: string;
  beforeParse?(source: string): string;
  afterParse?(ast: DocumentNode): DocumentNode;
  onError?(error: Error, source: string): Error | null;
}

class ExtendedTamlParser {
  private plugins: TamlParserPlugin[] = [];

  addPlugin(plugin: TamlParserPlugin) {
    this.plugins.push(plugin);
    return this;
  }

  parse(source: string, options?: ParseOptions): DocumentNode {
    let processedSource = source;

    // Apply beforeParse plugins
    for (const plugin of this.plugins) {
      if (plugin.beforeParse) {
        processedSource = plugin.beforeParse(processedSource);
      }
    }

    try {
      let ast = parseTaml(processedSource, options);

      // Apply afterParse plugins
      for (const plugin of this.plugins) {
        if (plugin.afterParse) {
          ast = plugin.afterParse(ast);
        }
      }

      return ast;
    } catch (error) {
      // Apply error handling plugins
      for (const plugin of this.plugins) {
        if (plugin.onError) {
          const handledError = plugin.onError(error, source);
          if (handledError) {
            throw handledError;
          }
        }
      }
      throw error;
    }
  }
}

// Example plugins
const preprocessorPlugin: TamlParserPlugin = {
  name: "preprocessor",
  beforeParse: (source) => {
    // Convert legacy format
    return source.replace(/\[ERROR\]/g, "<red>[ERROR]</red>");
  },
};

const validationPlugin: TamlParserPlugin = {
  name: "validation",
  afterParse: (ast) => {
    // Add validation metadata
    const elementCount = getElementsWithTag(ast, "red").length;
    if (elementCount > 10) {
      console.warn("High number of error elements detected");
    }
    return ast;
  },
};

// Usage
const extendedParser = new ExtendedTamlParser()
  .addPlugin(preprocessorPlugin)
  .addPlugin(validationPlugin);

const ast = extendedParser.parse("[ERROR] Connection failed");

Contributing

We welcome contributions! Please see our Contributing Guide for details.

Development Setup

# Clone the repository
git clone https://github.com/suin/taml-parser.git
cd taml-parser

# Install dependencies
bun install

# Run tests
bun test

# Build the project
bun run build

# Lint and format
bun run lint
bun run format

Testing

The project uses Bun for testing with comprehensive test coverage:

# Run all tests
bun test

# Run tests in watch mode
bun test --watch

# Run specific test files
bun test parser.test.ts
bun test tokenizer.test.ts
bun test validator.test.ts
bun test errors.test.ts

# Run with coverage
bun test --coverage

Test Coverage

The parser is thoroughly tested with:

Unit Tests: Core parsing functionality, tokenization, validation
Integration Tests: End-to-end parsing scenarios with real-world examples
Error Handling: All error types and edge cases
Performance Tests: Memory usage and parsing speed benchmarks
Edge Cases: Malformed input, deeply nested structures, large documents

Code Quality Standards

# Type checking
bun run build

# Linting
bun run lint

# Code formatting
bun run format

# Run all quality checks
bun run build && bun run lint && bun test

Adding New Features

When contributing new features:

Add tests first - Write comprehensive tests for new functionality
Update documentation - Include examples and API documentation
Consider performance - Ensure new features don't degrade parsing speed
Maintain compatibility - Follow semantic versioning for breaking changes
Add error handling - Provide clear error messages for invalid input

Reporting Issues

When reporting bugs or requesting features:

Provide examples - Include sample TAML input that demonstrates the issue
Include error messages - Copy the full error message and stack trace
Specify environment - Node.js version, operating system, package version
Expected behavior - Describe what you expected to happen
Actual behavior - Describe what actually happened

License

MIT © suin

Part of the TAML ecosystem - Visit the TAML Specification for more information about the Terminal ANSI Markup Language.

Name		Name	Last commit message	Last commit date
Latest commit History 4 Commits
.github/workflows		.github/workflows
ts		ts
.envrc		.envrc
.gitignore		.gitignore
LICENSE		LICENSE
README.md		README.md
biome.json		biome.json
bun.lock		bun.lock
devbox.json		devbox.json
devbox.lock		devbox.lock
package.json		package.json
tsconfig.build.json		tsconfig.build.json
tsconfig.json		tsconfig.json
tsconfig.test.json		tsconfig.test.json

License

suin/taml-parser

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@taml/parser

TAML Ecosystem

Package Dependencies

Related Packages

Core Infrastructure

Input/Output Tools

Integration Packages

Installation

npm

yarn

pnpm

bun

TypeScript Setup

Quick Start

Core Concepts

Parser Architecture

1. Tokenization

2. Validation

3. AST Construction

4. Error Handling

Supported TAML Features

Standard Colors

Bright Colors

Text Styles

Error Handling Approach

Usage Examples

Basic Parsing

Simple Color Tags

Text Formatting

Complex Nesting

Nested Formatting

Terminal Output Simulation

Error Recovery Patterns

Safe Parsing with Error Handling

Validation Before Parsing

Real-World Use Cases

Log File Processing

Terminal Command Documentation

Integration with TAML Ecosystem

With AST Utilities

With Encoder

With React Components

With CLI Tools

Complete Processing Pipeline

API Reference

Main Functions

Parse Options

ParseOptions Interface

Advanced Usage

TamlParser Class

Tokenization

Validation

Error Handling

Error Types

Error Context

Common Error Patterns

Invalid Tag Names

Nesting Issues

Malformed Syntax

Advanced Topics

Performance Considerations

Optimization Features

Benchmarks

Memory Usage

Optimization Tips

Error Handling Patterns

Graceful Error Recovery

Batch Processing with Error Handling

Custom Error Handling

Integration Patterns

Parser Factory Pattern

Streaming Parser for Large Documents

Plugin Architecture

Contributing

`ParseOptions` Interface

`TamlParser` Class