Extract Command

The extract command retrieves complete code blocks from files with full context. It's designed to extract functions, classes, and other code structures based on file locations, line numbers, or symbol names.

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TL;DR

# Extract function at line 42
probe extract src/auth.rs:42

# Extract by symbol name
probe extract src/auth.rs#login_user

# Extract from git diff
git diff | probe extract --diff

# Extract with LLM prompt template
probe extract src/api.ts:100 --prompt engineer

# Copy to clipboard
probe extract src/utils.py:25 --to-clipboard

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Basic Syntax

probe extract <FILE:LINE> [OPTIONS]
probe extract <FILE#SYMBOL> [OPTIONS]
probe extract <FILE:START-END> [OPTIONS]

Extraction Methods

Method	Syntax	Description
Line-based	file.rs:42	Extract block containing line 42
Symbol-based	file.rs#function_name	Extract named symbol
Range-based	file.rs:10-20	Extract lines 10-20
Multiple files	file1.rs:10 file2.ts:20	Extract from multiple locations

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Input Sources

From Arguments

# Single file
probe extract src/main.rs:42

# Multiple files
probe extract src/auth.rs:10 src/user.rs:50 src/api.rs:100

# Mixed methods
probe extract src/auth.rs:42 src/user.rs#User src/api.rs:10-50

From Clipboard

# Read file:line references from clipboard
probe extract --from-clipboard

From File

# Read from a file containing references
probe extract --input-file references.txt

# From error logs
cat error.log | grep -E '\w+\.\w+:\d+' | probe extract --input-file -

From Git Diff

# Extract changed code blocks
git diff | probe extract --diff

# Extract from staged changes
git diff --cached | probe extract --diff

# Extract from specific commit
git show HEAD~1 | probe extract --diff

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Command Options

Context Options

Flag	Type	Default	Description
-c, --context	Number	0	Lines of context before/after
-k, --keep-input	Boolean	false	Keep and display original input

# Add 5 lines of context
probe extract src/auth.rs:42 --context 5

# Keep original stack trace visible
probe extract --input-file error.log --keep-input

Output Options

Flag	Type	Default	Description
-o, --format	String	"color"	Output format
--dry-run	Boolean	false	Output only file:line references
-t, --to-clipboard	Boolean	false	Copy output to clipboard

Available Formats:

Format	Description
color	Syntax-highlighted terminal output
markdown	Markdown with code fences
plain	Plain text without formatting
json	Structured JSON output
xml	Structured XML output
outline-xml	XML-formatted hierarchical outline
outline-diff	Diff-style outline format

# Markdown for documentation
probe extract src/api.rs:42 --format markdown

# JSON for tooling
probe extract src/auth.rs:100 --format json

# Copy to clipboard
probe extract src/utils.ts:25 --to-clipboard

Input Options

Flag	Type	Default	Description
-f, --from-clipboard	Boolean	false	Read from clipboard
-F, --input-file	String	-	Read from file
--diff	Boolean	false	Parse input as git diff

# From clipboard (IDE stack trace)
probe extract --from-clipboard

# From error log file
probe extract --input-file crash.log

# From piped git diff
git diff HEAD~3 | probe extract --diff

LLM Prompt Templates

Flag	Type	Default	Description
--prompt	String	-	System prompt template
--instructions	String	-	User instructions for LLM

Built-in Templates:

Template	Description
engineer	Senior software engineer focus (code changes)
architect	Software architect focus (design decisions)
code-review	Code review focus
code-review-template	Code review with custom rules
Custom path	Load template from file

# Engineer prompt for code modifications
probe extract src/auth.rs:42 --prompt engineer

# Code review with instructions
probe extract src/api.ts:100 --prompt code-review --instructions "Check for security issues"

# Custom template file
probe extract src/db.rs:50 --prompt ./prompts/database-review.md

Filter Options

Flag	Type	Default	Description
--allow-tests	Boolean	false	Include test files
-i, --ignore	String[]	-	Patterns to ignore
--no-gitignore	Boolean	false	Don't respect .gitignore

# Include test utilities
probe extract tests/helpers.rs:10 --allow-tests

# Ignore generated files
probe extract src/generated.ts:50 --ignore "*.generated.*"

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Output Examples

Color Output (Default)

probe extract src/auth/login.ts:15

─────────────────────────────────────────
📄 src/auth/login.ts:15-42
─────────────────────────────────────────
export async function login(
  email: string,
  password: string
): Promise<User> {
  const user = await db.findUserByEmail(email);
  if (!user) {
    throw new AuthError('User not found');
  }

  const valid = await bcrypt.compare(password, user.passwordHash);
  if (!valid) {
    throw new AuthError('Invalid password');
  }

  return generateSession(user);
}
─────────────────────────────────────────

JSON Output

probe extract src/auth/login.ts:15 --format json

{
  "blocks": [
    {
      "file": "src/auth/login.ts",
      "lines": { "start": 15, "end": 42 },
      "symbol": "login",
      "type": "function",
      "code": "export async function login(...) {...}",
      "language": "typescript"
    }
  ],
  "metadata": {
    "total_blocks": 1,
    "total_lines": 28
  }
}

Markdown Output

probe extract src/auth/login.ts:15 --format markdown

## src/auth/login.ts

### `login` (lines 15-42)

```typescript
export async function login(
  email: string,
  password: string
): Promise<User> {
  // ... implementation
}
```

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Common Patterns

Debugging Workflows

# Extract from error stack trace
cat error.log | probe extract --input-file -

# Extract from clipboard (copy stack trace from IDE)
probe extract --from-clipboard --format markdown

# Extract with context for debugging
probe extract src/api.ts:142 --context 10

Code Review

# Extract changed functions for review
git diff main | probe extract --diff --prompt code-review

# Review specific file changes
git diff HEAD~1 -- src/auth.ts | probe extract --diff --prompt code-review \
  --instructions "Focus on authentication security"

Documentation

# Generate markdown documentation
probe extract src/api/endpoints.ts:* --format markdown > docs/api.md

# Extract public API for docs
probe extract src/index.ts#exportedFunction --format markdown

AI Integration

# Prepare code for AI analysis
probe extract src/complex.rs:100 --prompt architect | llm "Review this design"

# Extract and copy for ChatGPT
probe extract src/auth.rs:42 --prompt engineer --to-clipboard

# JSON for programmatic AI tools
probe extract src/api.ts:50 --format json | ai-tool analyze

Multiple Extractions

# Extract related code blocks
probe extract \
  src/models/user.ts:15 \
  src/services/auth.ts:42 \
  src/api/login.ts:100 \
  --format markdown

# From a list of references
cat important-functions.txt | xargs probe extract --format json

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Symbol Extraction

Extract code by symbol name rather than line number:

# Extract a function
probe extract src/auth.rs#authenticate_user

# Extract a class
probe extract src/models/user.py#UserModel

# Extract a method
probe extract src/api/handler.ts#handleRequest

# Extract an interface
probe extract src/types.ts#ApiResponse

Note: Symbol extraction uses tree-sitter to find the named symbol in the AST.

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Git Diff Integration

The --diff flag parses git diff output and extracts the changed code blocks:

# Current uncommitted changes
git diff | probe extract --diff

# Staged changes
git diff --cached | probe extract --diff

# Changes in a PR
git diff main...feature-branch | probe extract --diff

# Changes in last N commits
git diff HEAD~5 | probe extract --diff

# Specific file changes
git diff HEAD~1 -- src/auth.ts | probe extract --diff

The extractor identifies:

• Modified functions/methods
• Added code blocks
• Changed class definitions
• Updated configuration blocks

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Performance Tips

1. Use symbol extraction when you know the function name
2. Use --dry-run to preview what will be extracted
3. Batch extractions with multiple file arguments
4. Use --context 0 for minimal output (default)

# Preview extraction targets
probe extract src/large-file.ts:100 --dry-run

# Batch extraction (faster than multiple commands)
probe extract file1.ts:10 file2.ts:20 file3.ts:30

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Related Documentation

• Search Command - Find code to extract
• Query Command - AST-based code queries
• Output Formats - Format specifications
• AI Integration - Using extract with AI tools