# Value Checking

Functions for handling null/undefined values and checking if values exist.

***

## COALESCE

Returns the first defined (non-undefined) argument. Useful for fallback values.

**Syntax:** `COALESCE(value1, value2, value3, ...)`

**Example:**

```
COALESCE({item's Optional}, {item's Default}, "N/A")
```

**Result:** First non-undefined value among the arguments.

**Example:**

```
COALESCE(undefined, 0)
```

**Result:** `0`

***

## HAS\_VALUE / VALUE\_EXISTS

Returns `"True"` or `"False"` based on whether the input has a meaningful value.

**Syntax:** `HAS_VALUE(input)` or `VALUE_EXISTS(input)`

**Behavior:**

| Input                | Result    |
| -------------------- | --------- |
| Non-empty string     | `"True"`  |
| Empty string         | `"False"` |
| Number (including 0) | `"True"`  |
| NaN                  | `"False"` |
| Non-empty array      | `"True"`  |
| Empty array          | `"False"` |
| Object with keys     | `"True"`  |
| null/undefined       | `"False"` |

**Example:**

```
HAS_VALUE({item's Status})
```

**Result:** `"True"` if Status has a value; `"False"` if empty.

**Example:**

```
IF(HAS_VALUE({item's Notes}), {item's Notes}, "No notes")
```

**Result:** Notes value if present; otherwise `"No notes"`.


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