Using {} inside of a regex makes the function think you're trying to find a repeating value when it looks like you didn't intend to use the {} as a regex operator, but instead you intended it to evaluate $value, which isn't the case inside of a regex.
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Using {} inside of a regex makes the function think you're trying to find a repeating value when it looks like you didn't intend to use the {} as a regex operator, but instead you intended it to evaluate $value, which isn't the case inside of a regex.