Find Replace Skill

Modern find-and-replace using sd (simpler than sed) and batch replacement patterns.

Triggers

sd, find replace, batch replace, sed replacement, string replacement, rename

sd Basics

Simple Replacement

# Replace in file (in-place)
sd 'oldText' 'newText' file.txt

# Replace in multiple files
sd 'oldText' 'newText' *.js

# Preview without changing (pipe instead of file)
cat file.txt | sd 'old' 'new'

sd vs sed Comparison

sed	sd	Notes
sed 's/old/new/g'	sd 'old' 'new'	Global by default
sed -i 's/old/new/g'	sd 'old' 'new' file	In-place by default
sed 's/\./dot/g'	sd '\.' 'dot'	Same escaping
sed 's#path/to#new/path#g'	sd 'path/to' 'new/path'	No delimiter issues

Common Patterns

Variable Rename

# Rename variable across files
sd 'oldVarName' 'newVarName' src/**/*.ts

# Preview first with rg
rg 'oldVarName' src/
# Then apply
sd 'oldVarName' 'newVarName' $(rg -l 'oldVarName' src/)

Function Rename

# Rename function (all usages)
sd 'getUserData' 'fetchUserProfile' src/**/*.ts

# More precise with word boundaries
sd '\bgetUserData\b' 'fetchUserProfile' src/**/*.ts

Import Path Update

# Update import paths
sd "from '../utils'" "from '@/utils'" src/**/*.ts
sd "require\('./config'\)" "require('@/config')" src/**/*.js

String Quotes

# Single to double quotes
sd "'" '"' file.json

# Template literals
sd '"\$\{(\w+)\}"' '`${$1}`' src/**/*.ts

Regex Patterns

Capture Groups

# Reorder parts
sd '(\w+)@(\w+)\.com' '$2/$1' emails.txt
# john@example.com → example/john

# Wrap in function
sd 'console\.log\((.*)\)' 'logger.info($1)' src/**/*.js

Optional Matching

# Handle optional whitespace
sd 'function\s*\(' 'const fn = (' src/**/*.js

Multiline (with -s flag)

# Replace across lines
sd -s 'start\n.*\nend' 'replacement' file.txt

Batch Workflows

Find Then Replace

# 1. Find files with pattern
rg -l 'oldPattern' src/

# 2. Preview replacements
rg 'oldPattern' -r 'newPattern' src/

# 3. Apply to found files
sd 'oldPattern' 'newPattern' $(rg -l 'oldPattern' src/)

With fd

# Replace in specific file types
fd -e ts -x sd 'old' 'new' {}

# Replace in files matching name pattern
fd 'config' -e json -x sd '"dev"' '"prod"' {}

Dry Run Pattern

# Safe workflow: preview → verify → apply

# Step 1: List affected files
rg -l 'oldText' src/

# Step 2: Show what will change
rg 'oldText' -r 'newText' src/

# Step 3: Apply (only after verification)
sd 'oldText' 'newText' $(rg -l 'oldText' src/)

# Step 4: Verify
rg 'oldText' src/  # Should return nothing
git diff           # Review changes

Special Characters

Escaping

# Literal dot
sd '\.' ',' file.txt

# Literal brackets
sd '\[' '(' file.txt

# Literal dollar sign
sd '\$' '€' file.txt

# Literal backslash
sd '\\' '/' paths.txt

Common Escapes

Character	Escape
.	\.
*	\*
?	\?
[ ]	\[ \]
( )	\( \)
{ }	\{ \}
$	\$
^	\^
\	\\

Real-World Examples

Update Package Version

sd '"version": "\d+\.\d+\.\d+"' '"version": "2.0.0"' package.json

Fix File Extensions in Imports

sd "from '(\./[^']+)'" "from '\$1.js'" src/**/*.ts

Convert CSS Class Names

# kebab-case to camelCase (simple cases)
sd 'class="(\w+)-(\w+)"' 'className="$1$2"' src/**/*.jsx

Update API Endpoints

sd '/api/v1/' '/api/v2/' src/**/*.ts
sd 'api\.example\.com' 'api.newdomain.com' src/**/*.ts

Remove Console Logs

# Remove entire console.log statements
sd 'console\.log\([^)]*\);?\n?' '' src/**/*.ts

Add Prefix to IDs

sd 'id="(\w+)"' 'id="prefix-$1"' src/**/*.html

Tips

Tip	Why
Always preview with rg -r first	Avoid accidental mass changes
Use git diff after	Verify changes before commit
Prefer specific patterns	\bword\b over word to avoid partial matches
Quote patterns	Avoid shell interpretation
Use fd to target files	More precise than **/*.ext

Installation

# Cargo (Rust)
cargo install sd

# Homebrew (macOS)
brew install sd

# Windows (scoop)
scoop install sd