Built-in Functions Reference

Complete reference for built-in functions available in TinySystems expressions.

Time Functions

now()

Returns the current timestamp in nanoseconds since Unix epoch.

Syntax:

now()

Returns: number (nanoseconds)

Examples:

{{now()}}
// Result: 1705312200000000000

timestamp: "{{now()}}"
// Result: "1705312200000000000"

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RFC3339()

Formats a timestamp as an RFC3339 string.

Syntax:

RFC3339(timestamp)

Parameters:

Name	Type	Description
timestamp	number	Unix timestamp in nanoseconds

Returns: string (RFC3339 formatted)

Examples:

{{RFC3339(now())}}
// Result: "2024-01-15T10:30:00Z"

{{RFC3339($.createdAt)}}
// Result: "2024-01-10T14:22:35Z"

---

Type Conversion Functions

string()

Converts a value to string.

Syntax:

string(value)

Parameters:

Name	Type	Description
value	any	Value to convert

Returns: string

Conversion Rules:

Input	Output
42	"42"
3.14	"3.14"
true	"true"
false	"false"
null	"null"

Examples:

{{string($.count)}}
// 42 → "42"

{{string($.active)}}
// true → "true"

{{'ID-' + string($.id)}}
// "ID-123"

---

int()

Converts a value to integer.

Syntax:

int(value)

Parameters:

Name	Type	Description
value	any	Value to convert

Returns: number (integer)

Conversion Rules:

Input	Output
"42"	42
3.7	3
true	1
false	0
"abc"	0 or NaN

Examples:

{{int($.stringNumber)}}
// "42" → 42

{{int($.floatValue)}}
// 3.7 → 3

---

String Functions

upper()

Converts string to uppercase.

Syntax:

upper(string)

Parameters:

Name	Type	Description
string	string	String to convert

Returns: string

Examples:

{{upper($.name)}}
// "alice" → "ALICE"

{{upper('hello')}}
// "HELLO"

---

lower()

Converts string to lowercase.

Syntax:

lower(string)

Parameters:

Name	Type	Description
string	string	String to convert

Returns: string

Examples:

{{lower($.email)}}
// "USER@EXAMPLE.COM" → "user@example.com"

{{lower('HELLO')}}
// "hello"

---

trim()

Removes whitespace from both ends of a string.

Syntax:

trim(string)

Parameters:

Name	Type	Description
string	string	String to trim

Returns: string

Examples:

{{trim($.input)}}
// "  hello  " → "hello"

{{trim('  world  ')}}
// "world"

---

len()

Returns the length of a string or array.

Syntax:

len(value)

Parameters:

Name	Type	Description
value	string or array	Value to measure

Returns: number

Examples:

// String length
{{len($.name)}}
// "Alice" → 5

// Array length
{{len($.items)}}
// [1, 2, 3] → 3

// Empty check
{{len($.text) > 0}}
// true if not empty

---

Math Functions

round()

Rounds to nearest integer.

Syntax:

round(number)

Parameters:

Name	Type	Description
number	number	Number to round

Returns: number

Rounding Rules:

Input	Output
3.2	3
3.5	4
3.7	4
-2.5	-2

Examples:

{{round($.price)}}
// 19.99 → 20

{{round($.average)}}
// 3.14159 → 3

---

floor()

Rounds down to nearest integer.

Syntax:

floor(number)

Parameters:

Name	Type	Description
number	number	Number to floor

Returns: number

Examples:

{{floor(3.9)}}
// 3

{{floor(-2.1)}}
// -3

{{floor($.value)}}

---

ceil()

Rounds up to nearest integer.

Syntax:

ceil(number)

Parameters:

Name	Type	Description
number	number	Number to ceil

Returns: number

Examples:

{{ceil(3.1)}}
// 4

{{ceil(-2.9)}}
// -2

{{ceil($.quantity)}}

---

abs()

Returns absolute value.

Syntax:

abs(number)

Parameters:

Name	Type	Description
number	number	Number

Returns: number

Examples:

{{abs(-5)}}
// 5

{{abs($.difference)}}

{{abs($.a - $.b)}}

---

Function Quick Reference

Function	Parameters	Returns	Description
now()	none	number	Current timestamp (ns)
RFC3339(ts)	timestamp	string	Format timestamp
string(v)	any	string	Convert to string
int(v)	any	number	Convert to integer
upper(s)	string	string	Uppercase
lower(s)	string	string	Lowercase
trim(s)	string	string	Remove whitespace
len(v)	string/array	number	Length
round(n)	number	number	Round to nearest
floor(n)	number	number	Round down
ceil(n)	number	number	Round up
abs(n)	number	number	Absolute value

---

Usage Examples

Timestamp Formatting

created: "{{RFC3339(now())}}"
// "2024-01-15T10:30:00Z"

Data Normalization

email: "{{lower(trim($.email))}}"
// " USER@EXAMPLE.COM " → "user@example.com"

Calculations

discountedPrice: {{round($.price * 0.9 * 100) / 100}}
// Round to 2 decimal places

Conditional with Functions

hasContent: {{len($.text) > 0}}
displayName: "{{len($.nickname) > 0 ? $.nickname : $.fullName}}"

Combined Operations

summary: "{{upper($.name)}} - Items: {{len($.items)}} - Total: ${{round($.total)}}"
// "ALICE - Items: 5 - Total: $150"

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Error Handling

Invalid Arguments

Scenario	Behavior
Wrong type	Type coercion attempted
null/undefined	Returns null or empty
Missing argument	Error or undefined

Best Practices

# Provide defaults before function calls
name: "{{upper($.name || 'unknown')}}"

# Check for existence
length: "{{$.items != null ? len($.items) : 0}}"