Operators Quick Reference

Complete alphabetical reference of all operators in JSONEval-Rs.

Core & Variable Access

Operator Description Example
var Access variable from data {"var": "user.name"}
$ref / ref JSON Schema reference {"$ref": "path"}
Literals null, bool, number, string, array 42, "text", [1,2,3]

Logical Operators

Operator Description Example
and Logical AND {"and": [cond1, cond2]}
or Logical OR {"or": [val1, val2]}
not / ! Logical NOT {"!": value}
if Conditional {"if": [cond, then, else]}
xor Exclusive OR {"xor": [a, b]}
ifnull Null coalescing {"ifnull": [val, default]}
isempty Check if empty {"isempty": value}
empty Empty string literal {"empty": null}

Comparison Operators

Operator Description Example
== Equal (loose) {"==": [a, b]}
=== Strict equal {"===": [a, b]}
!= Not equal (loose) {"!=": [a, b]}
!== Strict not equal {"!==": [a, b]}
< Less than {"<": [a, b]}
<= Less than or equal {"<=": [a, b]}
> Greater than {">": [a, b]}
>= Greater than or equal {">=": [a, b]}

Arithmetic Operators

Operator Description Example
+ Addition {"+": [1, 2, 3]}
- Subtraction / Negation {"-": [10, 3]}
* Multiplication {"*": [2, 3, 4]}
/ Division {"/": [10, 2]}
% Modulo {"%": [7, 3]}
^ / pow Power {"^": [2, 3]}

Math Functions

Operator Description Example
abs Absolute value {"abs": -5}
max Maximum value {"max": [1, 5, 3]}
min Minimum value {"min": [1, 5, 3]}
round Round to decimals {"ROUND": [3.14159, 2]}
roundup Round up {"ROUNDUP": [3.1, 0]}
rounddown Round down {"ROUNDDOWN": [3.9, 0]}
ceiling Ceiling to multiple {"CEILING": [4.3, 0.5]}
floor Floor to multiple {"FLOOR": [4.7, 0.5]}
trunc Truncate decimals {"TRUNC": [8.9, 2]}
mround Round to multiple {"MROUND": [10, 3]}

String Operators

Operator Description Example
cat Concatenate {"cat": ["Hello", " ", "World"]}
concat Concatenate (alias) {"CONCAT": [a, b, c]}
substr Substring {"substr": [text, 0, 5]}
search Find substring {"SEARCH": ["find", "text"]}
left Left characters {"LEFT": [text, 5]}
right Right characters {"RIGHT": [text, 5]}
mid Middle characters {"MID": [text, 1, 5]}
len / length String/array length {"len": text}
splittext Split and get index {"splittext": [text, ",", 0]}
splitvalue Split to array {"splitvalue": [text, ","]}
stringformat Format number {"STRINGFORMAT": [1234.5, 2, "$"]}

Date Functions

Operator Description Example
today Current date {"today": null}
now Current datetime {"now": null}
year Extract year {"YEAR": date}
month Extract month {"MONTH": date}
day Extract day {"DAY": date}
date Construct date {"DATE": [2024, 1, 15]}
dateformat Format date {"DATEFORMAT": [date, "short"]}
days Days between {"DAYS": [end, start]}
yearfrac Year fraction {"YEARFRAC": [start, end]}
datedif Date difference {"DATEDIF": [start, end, "Y"]}

Array Operators

Operator Description Example
map Transform array {"map": [array, logic]}
filter Filter array {"filter": [array, logic]}
reduce Reduce array {"reduce": [array, logic, init]}
all All match {"all": [array, logic]}
some Some match {"some": [array, logic]}
none None match {"none": [array, logic]}
merge Merge arrays {"merge": [arr1, arr2]}
in Contains value {"in": [val, array]}
sum Sum values {"SUM": [array]}
for Loop and build {"FOR": [1, 5, logic]}
multiplies Flatten and multiply {"MULTIPLIES": [vals]}
divides Flatten and divide {"DIVIDES": [vals]}

Table/Lookup Operators

Operator Description Example
VALUEAT Get table value {"VALUEAT": [table, idx, col]}
MAXAT Last row value {"MAXAT": [table, col]}
INDEXAT Find index {"INDEXAT": [val, table, field]}
MATCH Match conditions {"MATCH": [table, val, field]}
MATCHRANGE Match in range {"MATCHRANGE": [table, min, max, val]}
CHOOSE Choose match {"CHOOSE": [table, val, field]}
FINDINDEX Complex find {"FINDINDEX": [table, conditions]}

Utility Operators

Operator Description Example
missing Check missing keys {"missing": ["key1", "key2"]}
missing_some Check minimum present {"missing_some": [1, keys]}
return Return raw value {"return": value}
RANGEOPTIONS Generate range options {"RANGEOPTIONS": [1, 100]}
MAPOPTIONS Map to options {"MAPOPTIONS": [table, lbl, val]}
MAPOPTIONSIF Conditional map {"MAPOPTIONSIF": [table, lbl, val, cond]}

Operator Aliases

Many operators have multiple names for compatibility:

Primary Aliases Style
var - Standard
$ref ref JSON Schema
not ! JavaScript
pow ^, ** Math
len length, LEN Excel/JS
cat concat, CONCAT JS/Excel

Case Sensitivity:

Special Variables

Available in specific contexts:

Variable Context Description
{"var": ""} map, filter, all, some, none Current element
{"var": "accumulator"} reduce Accumulated value
{"var": "current"} reduce Current element
{"var": "$iteration"} FOR Loop index

Common Patterns

Validation

{"if": [
  {"==": [{"length": {"missing": ["email", "name"]}}, 0]},
  "valid",
  "invalid"
]}

Calculation

{"round": [
  {"*": [{"var": "price"}, {"+": [1, {"var": "taxRate"}]}]},
  2
]}

Array Processing

{"map": [
  {"filter": [{"var": "users"}, {"var": "active"}]},
  {"var": "name"}
]}

Table Lookup

{"VALUEAT": [
  {"var": "table"},
  {"INDEXAT": [{"var": "key"}, {"var": "table"}, "id"]},
  "value"
]}

Date Calculation

{"-": [
  {"year": {"today": null}},
  {"year": {"var": "birthdate"}}
]}

Type Coercion

To Number

To Boolean (Truthiness)

To String

Configuration Options

Operators that respect configuration:

Option Affects Description
safe_nan_handling Math ops Converts NaN/Infinity to 0 or null
recursion_limit All Max nesting depth (default: 100)

Performance Tips

  1. Compile once, run many times
  2. Use automatic optimizations (flattening, short-circuit)
  3. Leverage fast paths for simple operations
  4. Cache expensive lookups
  5. Minimize nested operations when possible

Total Operators: 80+

This implementation extends standard JSON Logic with custom operators for Excel-like functions, table operations, and advanced date/string manipulation.