expression_if, expression_unless

{
    "description": "Prevent unintended Command+Q presses by ignoring it unless it's double-pressed",
    "manipulators": [
        {
            "type": "basic",
            "from": {
                "key_code": "q",
                "modifiers": {
                    "mandatory": ["command"],
                    "optional": ["any"]
                }
            },
            "to": [
                {
                    "key_code": "q",
                    "modifiers": ["command"]
                }
            ],
            "conditions": [
                {
                    "type": "expression_if",
                    "expression": "command_q_expiration > system.now.milliseconds"
                }
            ]
        },
        {
            "type": "basic",
            "from": {
                "key_code": "q",
                "modifiers": {
                    "mandatory": ["command"],
                    "optional": ["any"]
                }
            },
            "to": [
                {
                    "set_variable": {
                        "name": "command_q_expiration",
                        "expression": "system.now.milliseconds + 300"
                    }
                }
            ]
        }
    ]
}

{
    "type": "expression_if",
    "expression": expression
}