Data expressions

Learn how to use our data expressions to extract data from data sources.

Throughout the AdSigner app, data expressions are used to extract data from arbitrary data sources.
You can recognize the expression input field by the function icon:

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The label on the right will turn green if the expression is valid. The numbers tell how many values were extracted from the data source with the current expression.

invalid

When focusing on the input, a preview list will open showing the results of the expression for each item in the data source.
Clicking on an item in the preview list will display a popover displaying a tree structure of all available data.
Selecting a value in the popover will insert the corresponding expression.

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"Samuel Jones"

"Norman Price"

"Norris Steele"

name

.firstName	"Norman"
.lastName	"Price"
.fullName	"Norman Price"

title

"Paperboy"

"norman.price@adsigner.com"

Data expressions are also used in signature template code inside curly braces, for example { banner.src }.
Read more about custom signature templates here: Custom signature templates.

Mapping example

In this example, our data source is a list of 3 users. Each user is represented as an object with id, name, title and email properties. The preview list that opens when focusing on the input will display all users with the results of the expression.

Data source

[
    {
        "id": 1,
        "name": "Samuel Jones",
        "title": "Fireman",
        "email": "samuel.jones@adsigner.com"
    },
    {
        "id": 2,
        "name": "Norman Price",
        "title": "Paperboy",
        "email": "norman.price@adsigner.com"
    },
    {
        "id": 3,
        "name": "Norris Steele",
        "title": "Station Officer",
        "email": "norris.steele@adsigner.com"
    }
]

To extract the names of the users, we can simply use a name expression.

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"Samuel Jones"

"Norman Price"

"Norris Steele"

We can do the same for email.

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"samuel.jones@adsigner.com"

"norman.price@adsigner.com"

"norris.steele@adsigner.com"

Filter example

In some cases, like when configuring signature selection criteria, we might want to create a filter expression.
To target only users with the title "Fireman", we can use the following expression:

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true

false

Operators

View the full list of supported operators in the table below. Operators are sorted by precedence (higher precedence operators are evaluated before lower precedence ones).

Operator	Associativity	Description
`(...)`	None	Grouping
`f()`, `x.y`, `a[i]`	Left	Function call, property access, array indexing
`!`	Left	Factorial
`^`	Right	Exponentiation
`+`, `-`, `not`, `sqrt`, etc.	Right	Unary prefix operators
`*`, `/`, `%`	Left	Multiplication, division, remainder
`+`, `-`, `\|\|`	Left	Addition, subtraction, array/list concatenation
`==`, `!=`, `>=`, `<=`, `>`, `<`, `in`	Left	Equals, not equals, is element `in` collection
`and`	Left	Logical AND
`or`	Left	Logical OR
`x ? y : z`	Right	Ternary conditional (if `x` then `y` else `z`)

We can use operators to create more complex expressions, for example to join values.

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"Samuel Jones, Fireman"

"Norman Price, Paperboy"

"Norris Steele, Station Officer"

Functions

The following functions are supported.

Function	Description
`capitalize(string)`	Converts the first character of `string` to upper case and the remaining to lower case.
`deburr(string)`	Deburrs `string` by converting latin-1 supplementary letters to basic latin letters and removing combining diacritical marks.
`defaultTo(value, defaultValue)`	Checks `value` to determine whether a default value should be returned in its place. The `defaultValue` is returned if `value` is `NaN`, `null`, or `undefined`.
`includes(collection, target, fromIndex)`	Checks if `target` is in `collection` using SameValueZero for equality comparisons. If `fromIndex` is negative, it's used as the offset from the end of `collection`.
`indexOf(string, array)`	Returns the first index of string or array `array` matching the value `string`, or `-1` if not found.
`join(array, separator)`	Converts all elements in `array` into a string separated by `separator`.
`pad(string, length, chars)`	Pads `string` on the left and right sides if it's shorter than `length`. Padding characters are truncated if they can't be evenly divided by `length`.
`replace(string, pattern, replacement)`	Replaces matches for `pattern` in `string` with `replacement`.
`slice(array, start, end)`	Creates a slice of `array` from `start` up to, but not including, `end`.
`split(string, separator, limit)`	Splits `string` by `separator`. If `limit` is provided, only the first `limit` results are returned.
`trim(string, chars)`	Removes leading and trailing whitespace or specified `chars` from `string`.
`words(string, pattern)`	Splits `string` into an array of its words.

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false

true