search

The search function performs a predicate-based recursive search of the document tree. It allows you to find nodes that match specific conditions, not just by key name.

This makes search a more flexible and powerful alternative to the .. operator, which is shorthand for simple recursive key or index lookups.

---

Syntax

search(PREDICATE)

Where PREDICATE is a function that tests each node and returns true/false.

---

Behaviour

• Traverses the entire document tree, starting at the current node.

• Applies the given predicate to every node (objects, arrays, scalars).

• Returns all nodes that satisfy the predicate.

• Unlike .., search is not limited to key names or indices — it supports arbitrary conditions.

---

Predicates

Commonly used predicate functions include:

• has("KEY") — true if the node has the given key.

• $this == VALUE — true if the node equals VALUE .

• $key == "KEY" — true if the current key/index matches. For maps, $key is a string; for arrays, $key is an integer.

📌 Check the functions documentation for a full list.

---

Examples

Example Input

{
  "users": [
    { "id": 1, "name": "Alice" },
    { "id": 2, "name": "Bob" }
  ],
  "meta": {
    "active": true,
    "score": 42
  }
}

---

1. Search for Nodes with a Key

Find all nodes that contain a name field:

echo '{"users":[{"id":1,"name":"Alice"},{"id":2,"name":"Bob"}],"meta":{"active":true,"score":42}}' | dasel -i json 'search(has("name"))'

Output:

[
    {
        "id": 1,
        "name": "Alice"
    },
    {
        "id": 2,
        "name": "Bob"
    }
]

---

2. Search for Specific Values

Find all nodes where the value equals 42:

echo '{"users":[{"id":1,"name":"Alice"},{"id":2,"name":"Bob"}],"meta":{"active":true,"score":42}}' | dasel -i json 'search($this == 42)'

Output:

[
    42
]

---

3. Combining Predicates

Find all nodes that have both id and name keys:

echo '{"users":[{"id":1,"name":"Alice"},{"id":2,"name":"Bob"}],"meta":{"active":true,"score":42}}' | dasel -i json 'search(has("id") && has("name"))'

Output:

[
    {
        "id": 1,
        "name": "Alice"
    },
    {
        "id": 2,
        "name": "Bob"
    }
]

---

4. Search by Key Name Using $key

Find the value stored under a specific key:

echo '{"other": 1, "target": 42}' | dasel -i json 'search($key == "target")'

Output:

[
    42
]

---

Comparison to ..

• .. is shorthand for recursive key/index lookups:

  • ..name ≈ search(has("name"))

  • ..[0] ≈ search(has(0))

• search allows arbitrary logic, making it more powerful but also more verbose.

---

Notes

• search is ideal when you need fine-grained control over what you’re looking for.

• Use the recursive descent operator (..) for simple lookups by key or index.

• Both operators traverse the document tree recursively — the difference is specificity vs flexibility.