# P_isempty
## Syntax:
@isempty**({variable-or-value})**
## Use Case:
Returns `1` if empty, `0` otherwise. MudMaster-compatible: after `$`/`@` expansion the argument is usually a **value** (e.g. `@IsEmpty($0)`). If the argument names an existing variable, that variable's contents are checked instead.
## Arguments:
- **{variable-or-value}**: A variable name, or an already-expanded string value.
## Examples:
1. **/if {@isempty(input)} {/echo No data}**
    (Checks variable `input`)
2. **/if {@isempty($0) = 1} {/echo Missing arg}**
    (Checks the expanded wildcard value — MudMaster style)
## See Also:
@exists
