Ordo Expression Syntax
Operators
Comparison Operators
| Operator | Description | Example |
|---|
== | Equal | status == "active" |
!= | Not equal | status != "banned" |
> | Greater than | age > 18 |
>= | Greater or equal | balance >= 1000 |
< | Less than | price < 100 |
<= | Less or equal | level <= 5 |
Logical Operators
| Operator | Description | Example |
|---|
&& | And | age >= 18 && active == true |
|| | Or | vip == true || points > 1000 |
! | Not | !is_blocked |
Arithmetic Operators
| Operator | Description | Example |
|---|
+ | Addition | price + tax |
- | Subtraction | total - discount |
* | Multiplication | quantity * price |
/ | Division | total / count |
% | Modulo | index % 2 |
Field Access
Dot Notation
user.name
user.profile.level
order.items[0].price
Array Indexing
items[0]
matrix[1][2]
users[index]
Safe Access (coalesce)
coalesce(user.nickname, user.name, "Anonymous")
Built-in Functions
String Functions
| Function | Description | Example |
|---|
len(s) | String length | len(name) > 0 |
upper(s) | To uppercase | upper(code) == "VIP" |
lower(s) | To lowercase | lower(email) |
trim(s) | Trim whitespace | trim(input) |
starts_with(s, prefix) | Prefix match | starts_with(url, "https") |
ends_with(s, suffix) | Suffix match | ends_with(file, ".pdf") |
contains_str(s, sub) | Contains substring | contains_str(desc, "urgent") |
substring(s, start, end) | Extract substring | substring(code, 0, 3) |
Math Functions
| Function | Description | Example |
|---|
abs(n) | Absolute value | abs(diff) < 0.01 |
min(a, b, ...) | Minimum | min(price, max_price) |
max(a, b, ...) | Maximum | max(0, balance) |
floor(n) | Floor | floor(rating) |
ceil(n) | Ceiling | ceil(price) |
round(n) | Round | round(average) |
Array Functions
| Function | Description | Example |
|---|
len(arr) | Array length | len(items) > 0 |
sum(arr) | Sum of array | sum(prices) >= 100 |
avg(arr) | Average | avg(scores) > 60 |
count(arr) | Element count | count(orders) |
first(arr) | First element | first(results) |
last(arr) | Last element | last(history) |
Type Functions
| Function | Description | Example |
|---|
type(v) | Get type | type(value) == "string" |
is_null(v) | Is null | is_null(optional) |
is_number(v) | Is number | is_number(input) |
is_string(v) | Is string | is_string(data) |
is_array(v) | Is array | is_array(items) |
Conversion Functions
| Function | Description | Example |
|---|
to_int(v) | To integer | to_int(str_num) |
to_float(v) | To float | to_float(price) |
to_string(v) | To string | to_string(code) |
Time Functions
| Function | Description | Example |
|---|
now() | Current timestamp (seconds) | now() - created_at > 86400 |
now_millis() | Current timestamp (milliseconds) | now_millis() |
Conditional Expressions
if-then-else
if condition then value1 else value2
Examples:
if exists(discount) then price * (1 - discount) else price
if vip == true then 0.2 else 0.05
if age >= 18 then "adult" else "minor"
exists Check
if exists(user.nickname) then user.nickname else user.name
Nested Conditions
if tier == "gold" then 0.2
else if tier == "silver" then 0.1
else 0.05
Literals
Numbers
42 # Integer
3.14 # Float
-100 # Negative
Strings
"hello"
"it's ok"
"line1\nline2"
Booleans
true
false
Null
null
Rust API
Parsing Expressions
use ordo_core::prelude::*;
let parser = ExprParser::new();
let expr = parser.parse("age >= 18 && status == \"active\"")?;
Evaluation
let evaluator = Evaluator::new();
let context = Context::from_json(r#"{"age": 25, "status": "active"}"#)?;
let result = evaluator.eval(&expr, &context)?;
Compile to Bytecode
let compiler = ExprCompiler::new();
let compiled = compiler.compile(&expr)?;
let vm = BytecodeVM::new();
let result = vm.execute(&compiled, &context)?;
Key Files
crates/ordo-core/src/expr/parser.rs - Expression parsercrates/ordo-core/src/expr/eval.rs - Expression evaluationcrates/ordo-core/src/expr/functions.rs - Built-in functionscrates/ordo-core/src/expr/ast.rs - AST definitions
