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Formula - startswith
The startsWith function, one of the Logical functions in the Formula plugin for Search Field Expressions, returns true when the content starts with the expression (prefix).
Syntax
startsWith('expression', content [, content ...] [, matchAllValues])
Parameters
| Parameter | Required | Description |
|---|---|---|
'expression' |
✅ Yes | The prefix to look for, in single quotes, for example 'G'. |
content |
✅ Yes | The value or values to check: body, context, or another Formula function such as regex. When you give several content arguments, each of them must match. |
matchAllValues |
❌ No | Unquoted true or false (default). Applies when one content argument returns several values: false means at least one value must match, true means every value must match. A quoted 'true' is not the flag; it is compared as text. |
Returns
truewhen the content starts with the expression.- When it doesn't, there is no value: Test Expression shows Processed with warning: The provided expression yielded no result.
- When one content argument returns several values, one matching value is enough, unless
matchAllValuesistrue.
Quoting, nesting, and how content is resolved are described in the Formula language rules.
Examples
Example 1: Check the message body
Input
Message Body:
GMT
Formula
startsWith('G', body)
Result
true
The message body GMT starts with G, so startsWith returns true.
Example 2: Check a message context value
Input
Message Context:
| Key | Value |
|---|---|
id |
GMT |
Formula
startsWith('G', context('id'))
Result
true
The context value of id is GMT, which starts with G, so startsWith returns true.
Example 3: Check values extracted by another function
Input
Message Body:
GMT UTC
Formula
startsWith('U', regex('GMT|UTC', body))
Result
true
regex extracts GMT and UTC; UTC starts with U, and one match is enough, so startsWith returns true.
Example 4: Check several message context values
Input
Message Context:
| Key | Value |
|---|---|
id |
UMT |
id1 |
UZZ |
Formula
startsWith('U', context(regex('id.*')))
Result
true
context(regex('id.*')) returns the values of both keys, UMT and UZZ; they start with U, so startsWith returns true.