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$! Identifier - mIRC
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The $! identifier returns the input value that the script was just given via user input ($input, $? etc). This identifier may avoid using a variable.

Example[edit]

alias testme {
  $?="Type something"
  echo -a $!
}
After you execute the alias, via /testme, you will be prompted by an input box. Whatever input you put in that box, upon clicking OK, will be immediately echoed to your active window.
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