You did not set an actual command to use. The slash system needs a string that is your command, and when used, then calls the matching SlashCmdList entry.
Lua Code:
SLASH_NameOfEntry1="/command"
SLASH_NameOfEntry2="/cmd"
SLASH_NameOfEntry3="/alias"
SlashCmdList["NameOfEntry"]=function(textAfterCmd) --[[stuff]] end
You can make any number of different commands that call the same function, as long as the text between SLASH_ and the number is exactly the same as the entry in SlashCmdList, case sensitive. You only need just the number 1 line if you only want one command.