Function Overview¶

jpx provides 400+ functions organized into 31 categories.

Discovering Functions¶

List All Functions¶

jpx --list-functions

List by Category¶

jpx --list-category string
jpx --list-category math
jpx --list-category datetime

Get Function Details¶

jpx --describe upper

Categories¶

Category	Description	Count
Array	Functions for working with arrays: chunking, filtering, tran...	27
Color	Color manipulation and conversion functions.	8
Computing	Computing-related utility functions.	9
Date/Time	Functions for working with dates and times: parsing, formatt...	26
Duration	Functions for working with time durations.	8
Encoding	Encoding and decoding functions: Base64, hex, URL encoding, ...	10
Expression	Higher-order functions that work with JMESPath expressions a...	33
Format	Data formatting functions for numbers, currencies, and other...	6
Fuzzy	Fuzzy matching and string similarity functions.	9
Geolocation	Geolocation functions: distance calculation, coordinate pars...	10
Hash	Cryptographic hash functions: MD5, SHA family, and other has...	9
ID Generation	Functions for generating various types of unique identifiers...	3
JSON Patch	JSON Patch (RFC 6902) functions: applying patches, generatin...	3
Language	Natural language processing functions.	5
Math	Mathematical and statistical functions: arithmetic, rounding...	35
Multi-Match	Functions for matching multiple patterns or expressions in a...	10
Network	Network-related functions: IP addresses, CIDR notation, and ...	7
Object	Functions for working with JSON objects: merging, filtering ...	48
Path	File path manipulation functions.	7
Phonetic	Phonetic encoding functions for sound-based string matching.	9
Random	Functions for generating random values: numbers, strings, an...	5
Regular Expression	Regular expression functions: matching, replacing, splitting...	5
Semantic Versioning	Semantic versioning functions: parsing, comparing, and manip...	7
Standard JMESPath	These are the standard JMESPath functions as defined in the ...	26
String	Functions for string manipulation: case conversion, splittin...	36
Text	Text analysis and processing functions.	11
Type	Type conversion and checking functions.	13
URL	Functions for parsing and manipulating URLs and their compon...	6
Utility	General utility functions that don't fit other categories.	11
UUID	Functions for generating and working with UUIDs.	1
Validation	Functions for validating data: email, URL, UUID, and format ...	13

Function Syntax¶

Functions are called with parentheses:

function_name(arg1, arg2, ...)

Examples¶

# No arguments
echo '{}' | jpx 'now()'

# One argument
echo '{"name": "hello"}' | jpx 'upper(name)'

# Multiple arguments
echo '{"text": "hello world"}' | jpx 'split(text, ` `)'

# Literal arguments (use backticks)
echo '{}' | jpx 'range(`1`, `10`)'

Standard vs Extension Functions¶

Standard Functions (26)¶

These are part of the JMESPath specification and work in all implementations:

abs, avg, ceil, contains, ends_with, floor, join, keys, length, map, max, max_by, merge, min, min_by, not_null, reverse, sort, sort_by, starts_with, sum, to_array, to_number, to_string, type, values

Extension Functions (369)¶

These are jpx-specific and won't work in other JMESPath implementations.

Strict Mode¶

Use --strict to disable extension functions:

# This works
jpx --strict 'length(items)' -f data.json

# This fails (upper is an extension)
jpx --strict 'upper(name)' -f data.json