regex

Regular expression tools -- test, replace, and extract with Go regexp syntax.

Usage

openGyver regex [command] [flags]

Global Flags (inherited by all subcommands)

Flag	Short	Type	Default	Description
--json	-j	bool	false	Output as JSON
--help	-h			Help for regex

Subcommands

test

Test whether a regular expression matches the given input. Shows whether the pattern matches, all matched substrings, and any captured groups. Use --global/-g to find all matches in the input.

Arguments

Argument	Required	Description
pattern	Yes	The regular expression pattern (Go regexp syntax)
input	Yes	The input string to test against

Flags

Flag	Short	Type	Default	Description
--global	-g	bool	false	Find all matches (not just the first)
--help	-h			Help for test

Examples

# Test for digits in a string
openGyver regex test "\d+" "order 42 has 3 items"

# Find all matches globally
openGyver regex test --global "\d+" "order 42 has 3 items"

# Test with capture groups (global)
openGyver regex test --global "(\w+)@(\w+)" "alice@example bob@test"

# Test if a string starts with a pattern
openGyver regex test "^hello" "hello world"

# Test an email-like pattern
openGyver regex test "\w+@\w+\.\w+" "contact alice@example.com"

# JSON output for scripting
openGyver regex test "\d+" "order 42" --json

# Test with a complex pattern
openGyver regex test "^[A-Z][a-z]+ \d{4}$" "January 2024"

# Test for IP address pattern
openGyver regex test "\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}" "Server at 192.168.1.1 is up"

JSON Output Format (single match)

{
  "pattern": "\\d+",
  "input": "order 42 has 3 items",
  "matches": true,
  "match": "42",
  "groups": null
}

JSON Output Format (global match)

{
  "pattern": "\\d+",
  "input": "order 42 has 3 items",
  "matches": true,
  "all_matches": [
    { "match": "42" },
    { "match": "3" }
  ]
}

---

replace

Replace all occurrences of a regex pattern in the input string. The replacement string may include $1, $2, etc. for captured groups, and $0 for the entire match.

Arguments

Argument	Required	Description
pattern	Yes	The regular expression pattern to find
replacement	Yes	The replacement string (supports $1, $2, etc.)
input	Yes	The input string to perform replacement on

Flags

No subcommand-specific flags. Uses global flags only.

Examples

# Replace all digits with X
openGyver regex replace "\d+" "X" "order 42 has 3 items"
# Output: order X has X items

# Swap capture groups
openGyver regex replace "(\w+)@(\w+)" "\$2/\$1" "alice@example"
# Output: example/alice

# Collapse whitespace to single hyphens
openGyver regex replace "\s+" "-" "hello   world"
# Output: hello-world

# Remove all vowels
openGyver regex replace "[aeiouAEIOU]" "" "Hello World"

# JSON output
openGyver regex replace "\d+" "NUM" "item 42 costs 99" --json

# Wrap matches in brackets
openGyver regex replace "(\w+)" "[\$1]" "hello world"

# Normalize date format
openGyver regex replace "(\d{2})/(\d{2})/(\d{4})" "\$3-\$1-\$2" "01/15/2024"

# Strip HTML tags
openGyver regex replace "<[^>]+>" "" "<b>bold</b> and <i>italic</i>"

JSON Output Format

{
  "pattern": "\\d+",
  "replacement": "X",
  "input": "order 42 has 3 items",
  "result": "order X has X items"
}

---

extract

Extract all occurrences of a regex pattern from the input. Outputs one match per line. Input can come from a positional argument, --file/-f, or piped via stdin.

Arguments

Argument	Required	Description
pattern	Yes	The regular expression pattern to extract
input	No	The input string (or use --file / stdin)

Flags

Flag	Short	Type	Default	Description
--file	-f	string		Read input from a file
--help	-h			Help for extract

Examples

# Extract email addresses
openGyver regex extract "\w+@\w+\.\w+" "Contact alice@ex.com or bob@ex.com"

# Extract decimal numbers from a file
openGyver regex extract "\d+\.\d+" --file prices.txt

# Extract from piped input
echo "hello 123 world 456" | openGyver regex extract "\d+"

# Extract URLs
openGyver regex extract "https?://[^\s]+" "Visit https://example.com or http://test.org"

# Extract IP addresses from a log file
openGyver regex extract "\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}" --file access.log

# JSON output with match count
openGyver regex extract "\w+@\w+\.\w+" "alice@ex.com bob@ex.com" --json

# Extract hashtags
openGyver regex extract "#\w+" "Check out #golang and #devtools today"

# Extract dates from text
openGyver regex extract "\d{4}-\d{2}-\d{2}" "Created 2024-01-15, updated 2024-06-30"

JSON Output Format

{
  "pattern": "\\w+@\\w+\\.\\w+",
  "count": 2,
  "matches": ["alice@ex.com", "bob@ex.com"]
}