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moss edit ​

Structural code modification using tree-sitter for precise edits.

Target Syntax ​

Same as moss view:

  • path/to/file - Edit file
  • file/Symbol - Edit symbol
  • file/Parent/Child - Nested symbol
  • @alias - Edit alias target

Operations ​

OperationDescription
deleteDelete target symbol
replace <content>Replace target with new content
swap <other>Swap target with another symbol
insert <content> --at <pos>Insert content relative to target
move <dest> --at <pos>Move target to new location
copy <dest> --at <pos>Copy target to new location

Position (--at): before, after, prepend, append

Examples ​

bash
# Delete a function
moss edit src/old.rs/deprecated_fn delete

# Replace a function
moss edit src/main.rs/parse_config replace "fn parse_config() { todo!() }"

# Swap two functions
moss edit src/lib.rs/foo swap bar

# Insert before a symbol
moss edit src/lib.rs/Config insert "/// Documentation" --at before

# Move function into a class
moss edit src/api.rs/helper move MyClass --at append

# Copy function after another
moss edit src/lib.rs/original copy target --at after

Glob Patterns ​

Edit multiple symbols matching a pattern:

bash
# Delete all test_* functions
moss edit "file.py/test_*" delete --multiple

# Replace all foo_* with placeholder
moss edit "file.py/foo*" replace "pass" --multiple

# Insert comment before all matching symbols
moss edit "file.py/deprecated_*" insert "# DEPRECATED" --at before --multiple

# Move all matching symbols into a container
moss edit "file.py/helper_*" move HelperClass --at append --multiple

# Copy all matching symbols after a target
moss edit "file.py/util_*" copy utilities --at after --multiple

The --multiple flag is required when a pattern matches more than one symbol (safety measure).

Supported glob characters ​

  • * - Match any characters
  • ** - Match across path segments
  • ? - Match single character
  • [...] - Character class

Swap not supported with globs ​

The swap operation is not supported with glob patterns because the pairing semantics are ambiguous. If a pattern matches N symbols, what should each swap with? There's no clear answer.

bash
# This will error:
moss edit "file.py/foo*" swap "file.py/bar*" --multiple
# Error: 'swap' is not supported with glob patterns (ambiguous pairing)

For bulk swapping, use multiple individual swap commands or a script.

Options ​

Core ​

  • --dry-run - Show what would change without modifying
  • --multiple - Allow glob patterns matching multiple symbols
  • -y, --yes - Confirm destructive operations without prompting
  • -m, --message <TEXT> - Message describing the edit (for shadow git history)
  • -i, --case-insensitive - Case-insensitive symbol matching

Undo/Redo (Shadow Git) ​

  • --undo [<N>] - Undo the last N edits (default: 1)
  • --redo - Redo the last undone edit
  • --goto <REF> - Jump to a specific shadow commit
  • --file <PATH> - Undo changes only for specific file(s)
  • --cross-checkpoint - Allow undo across git commit boundaries
  • --force - Force undo even if files were modified externally

Batch ​

  • --batch <FILE> - Apply batch edits from JSON file (or - for stdin)

Output ​

  • --json - Output results as JSON
  • --jq <EXPR> - Filter JSON with jq expression
  • --pretty - Human-friendly output
  • --compact - Compact output without colors
  • -r, --root <PATH> - Root directory
  • --exclude <PATTERNS> - Exclude files matching patterns
  • --only <PATTERNS> - Only include files matching patterns

Structural vs Text Edits ​

moss edit uses tree-sitter for structural awareness:

  • Understands symbol boundaries
  • Preserves formatting
  • Handles nested structures

For simple text replacements, use standard tools (sed, Edit tool).