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$(eval)

Returns the output of custom JavaScript code using Fossabot's own JavaScript engine.

This variable is heavily limited to prevent abuse!

The maximum execution time of your code may not exceed 50ms, and there is a limit of one evaluation per action (command, keyword, or timer).

Parameters​

This variable takes one required parameter that is JavaScript code to be executed.

  • Please be aware of the following:
    • All code has to be wrapped in double quotes, example: $(eval "123 + 456")
    • Only single quotes can be used to indicate a string, example: $(eval "var test='hello world';test")
    • Both " and \ have to be escaped thrice when used within a string, example: $(eval "'Félix \\\"xQc\\\" Lengyel'")
    • Special characters have to be escaped twice, example: $(eval "'1 (blabla) 3'.replace(/\\(.*\\)/, '2')")

Example Usage​

  • A simple command with the name !sum and a response of the following:

    $(eval "$(index1) + $(index2)")

    If triggered by !sum 123 456, would return the following response:

    579

  • A more advanced command, a recreation of !uptime, with a response of the following:

    $(eval "var cname='$(channel.login)';var sname='$(sender.login)';var utime=`$(uptime)`; `${utime}` !== '[Error: Stream is offline.]' ? `${(sname === cname ? 'You have been' : cname + ' has been')} live for ${utime}.` : `${(sname === cname ? 'Your' : 'The')} stream is currently offline.`")

    If triggered in your own channel while you are offline, would return the following response:

    Your stream is currently offline.

    If triggered in your own channel while you are online, would return the following response:

    You have been live for 1 hour and 21 minutes.

    If triggered in Aiden's channel while he is offline, would return the following response:

    The stream is currently offline.

    If triggered in Aiden's channel while he is online, would return the following response:

    aiden has been live for 2 hours and 5 minutes.

Error Output​

  • In case of a standard JavaScript error, returns the specific JavaScript error.

  • In case an evaluation times out, returns the following:

    [Error: JavaScript evaluation timed out on remote server.]

  • In case an evaluation fails to execute, returns the following:

    [Error: Failed to execute JavaScript on remote server.]