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rainoftimerainoftime/pl-skills/language-server-protocol/SKILL.md

language-server-protocol

Skill17 starsChanged 9 months agoApache-2.0View on GitHub

Implements LSP servers for IDE features like go-to-definition, hover, and refactoring.

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    Use AST indexing for fast symbol lookup

    line 41

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SKILL.md

Language Server Protocol

Implements Language Server Protocol (LSP) servers that provide IDE features: autocomplete, go-to-definition, hover documentation, refactoring, and more.

When to Use This Skill

  • Building IDE support for programming languages
  • Adding language features to editors (VS Code, Emacs, Vim)
  • Implementing code navigation and refactoring
  • Creating language-aware tools

What This Skill Does

  1. LSP Server: Implements JSON-RPC based LSP protocol
  2. Text Documents: Manages source files with sync
  3. Code Intelligence: Provides hover, completion, definitions
  4. Refactorings: Implements code actions and rename

Key Concepts

ConceptDescription
Text Document SyncManaging document state
Request/NotificationLSP message types
LocationURI + Range for code positions
Code ActionEdit + Command for refactoring

Tips

  • Implement incremental sync for large files
  • Use AST indexing for fast symbol lookup
  • Cache expensive computations
  • Handle concurrent document changes

Related Skills

  • parser-generator - Parse source code
  • type-inference-engine - Type information for hover
  • abstract-interpretation-engine - Static analysis

Canonical References

ReferenceWhy It Matters
LSP SpecificationOfficial protocol docs
VS Code ExtensionsLanguage server examples
Tree-sitterIncremental parsing for LSP

Tradeoffs and Limitations

ApproachProsCons
Full indexAccurate, fast navSlow startup
On-demandFast startupSlower nav
Local cacheWorks offlineSync complexity

Assessment Criteria

CriterionWhat to Look For
Protocol compliancePasses LSP test suite
ResponsivenessFast response times
CompletenessAll key features

Quality Indicators

✅ Good: Protocol compliant, responsive, complete ⚠️ Warning: Some features missing, slow ❌ Bad: Protocol errors, crashes

Research Tools & Artifacts

Real-world LSP implementations:

ToolWhy It Matters
clangdC/C++ LSP server
rust-analyzerRust LSP server
pylspPython LSP server
goplsGo LSP server
typescript-language-serverTypeScript LSP

Key Servers

  • rust-analyzer: Fast Rust IDE support
  • clangd: C/C++ with clang

Research Frontiers

Current LSP research:

DirectionKey PapersChallenge
Performance"Fast LSP"Latency
Incremental"Incremental Analysis"Change impact
Remote"Remote LSP"Distributed

Hot Topics

  1. Language server for new langs: Building LSP for new languages
  2. WASM LSP: Running LSP in browser

Implementation Pitfalls

Common LSP bugs:

PitfallReal ExamplePrevention
SlowBlocked responsesAsync processing
MemoryLarge projectsIncremental
SyncStale resultsProper invalidation

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