Syntax

$onlyIf[condition]
$onlyIf[condition;errorMessage]

Parameters

Parameter	Description
condition	true, false, or a comparison (==, !=, >=, <=, >, <). If both sides are finite decimal numbers (12, -3.5, 1e3) the comparison is numeric and exact, with no rounding (12345678901234567890==12345678901234567891 is false); otherwise, hexadecimal such as 0x10 included, it is a text comparison. The < and > of a Discord mention, emoji, timestamp or command link (<@123>, <#123>, <a:name:123>, <t:123>) are part of the value, not operators ($onlyIf[$message[1]!=<@$authorID>] works). Anything else (for example 1 or an empty condition) is an error: Invalid condition: <condition>.
errorMessage	Optional. Text that replaces the response when the condition is false.

$onlyIf takes 1 or 2 arguments; a third argument is refused.

How It Works

1. The condition is evaluated.
2. If it is true, nothing happens and the script continues; the function returns an empty string.
3. If it is false, the script stops immediately (the rest of the script does not run, including inside loops and conditions).

Without a message

$onlyIf[condition]

The script stops, but what was already written (text, embeds, components) is still sent as the response. For example A$onlyIf[false]B sends A. If nothing was written, nothing is sent.

With a message

$onlyIf[condition;errorMessage]

The response written so far (text, embeds, components) is discarded and replaced by errorMessage, which is sent as the response (it is not sent to the channel separately). Messages already sent with $sendMessage are not affected. An empty errorMessage ($onlyIf[cond;]) discards the response and sends nothing.

If $suppressErrors[text] was used before, errorMessage is replaced by that text.

Examples

Input validation

$onlyIf[$message>=1;The number must be >= 1.]
$onlyIf[$message<=100;The number must be <= 100.]
Valid number: $message

Channel restriction

$onlyIf[$channelID==123456789012345678;This command can only be used in <#123456789012345678>.]

Comparison with $if / $stop

Without $onlyIf:

$if[$message<1]
The number must be >= 1.
$stop
$endif

With $onlyIf (equivalent when nothing else was written before):

$onlyIf[$message>=1;The number must be >= 1.]

The difference: $stop keeps what was already written, while $onlyIf[condition;message] discards it.