WoWInterface - Can someone fix this function?

hey guys, can someone fix this function?
ctrl + left click on chat frame to automatically report spammer
since 8.0, it's broken :(

Lua Code:

-- Ctrl + left click to report spamer
local _ChatFrame_OnHyperlinkShow = ChatFrame_OnHyperlinkShow;
function ChatFrame_OnHyperlinkShow (chatframe,link,text,button)
    if IsControlKeyDown() then
        local line = string.match(link,"player:[^:]+:(%d+):");
            if line then
                ReportPlayer("spam",line);
            return;
        end
    end
    return _ChatFrame_OnHyperlinkShow (chatframe,link,text,button);
end

error detail

Lua Code:

attempt to call global 'ReportPlayer' (a nil value)
Count: 1
 
Call Stack:
[C]: in function `ReportPlayer'
in function `ChatFrame_OnHyperlinkShow'
[string "*:OnHyperlinkClick"]:1: in function <[string "*:OnHyperlinkClick"]:1>