append_json()¶

Purpose¶

Appends an element to a JSON array or adds a key-value pair to a JSON object, returning a new object (the original is not modified).

Syntax¶

append_json(array, element)
append_json(object, key, value)

Parameters¶

For arrays (2 parameters):

array: The input JSON array to append to.
element: The element to add at the end of the array. Can be a string, number, or JSON value.

For objects (3 parameters):

object: The input JSON object to add a key-value pair to.
key: The key name (string) for the new property.
value: The value to associate with the key. Can be a string, number, or JSON value.

Return Value¶

Returns a new JSON array or object with the element/property added. The original input is not modified. Returns null if the input is invalid.

Examples¶

# Append to an array
set $.ret = parse_json('["error", "warning"]', "$!tags");
set $!tags = append_json($!tags, "info");
# Result: ["error", "warning", "info"]

# Add a property to an object (assign to a new variable)
set $.ret = parse_json('{"name": "test"}', "$!data");
set $!result = append_json($!data, "status", "active");
# Result in $!result: {"name": "test", "status": "active"}

# Chain multiple appends on arrays
set $.ret = parse_json('[]', "$!arr");
set $!arr = append_json($!arr, "first");
set $!arr = append_json($!arr, "second");
# Result: ["first", "second"]

See Also¶

split() - Split a string into a JSON array
parse_json() - Parse a JSON string

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